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diff --git a/src/battlecards/__init__.py b/src/battlecards/__init__.py
new file mode 100644
index 0000000..e5b416c
--- /dev/null
+++ b/src/battlecards/__init__.py
@@ -0,0 +1,13 @@
+"""Battle card generation module for AI bubble research."""
+from src.battlecards.card_templates import BattleCard, FIASection
+from src.battlecards.mini_charts import MiniChartEngine
+from src.battlecards.claim_extractor import ClaimExtractor
+from src.battlecards.generate_deck import DeckGenerator
+
+__all__ = [
+    "BattleCard",
+    "FIASection",
+    "MiniChartEngine",
+    "ClaimExtractor",
+    "DeckGenerator",
+]
diff --git a/src/battlecards/card_templates.py b/src/battlecards/card_templates.py
new file mode 100644
index 0000000..3c2a3ac
--- /dev/null
+++ b/src/battlecards/card_templates.py
@@ -0,0 +1,108 @@
+"""FIA (Fact-Impact-Act) battle card data model and Markdown assembly."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from typing import Optional
+
+
+@dataclass
+class FIASection:
+    """One section of a Fact-Impact-Act battle card.
+
+    Attributes:
+        name: Section name (e.g. "Fact", "Impact", "Act").
+        content: List of bullet-point strings.
+        chart_reference: Optional path to a mini-chart PNG file.
+    """
+
+    name: str
+    content: list[str]
+    chart_reference: Optional[str] = None
+
+
+@dataclass
+class BattleCard:
+    """A single FIA battle card for AI bubble research.
+
+    Attributes:
+        card_number: Integer 1-8 identifying the card.
+        title: Human-readable title for the card.
+        cluster: Cluster grouping — "bubble" or "value".
+        summary: One-line summary rendered as a Markdown blockquote.
+        fact: The Fact section of the FIA model.
+        impact: The Impact section of the FIA model.
+        act: The Act section of the FIA model.
+        sources: List of source references.
+        last_updated: Timestamp string for the card.
+    """
+
+    card_number: int
+    title: str
+    cluster: str
+    summary: str
+    fact: FIASection
+    impact: FIASection
+    act: FIASection
+    sources: list[str]
+    last_updated: str
+
+
+def render_card(card: BattleCard) -> str:
+    """Assemble a BattleCard into a Markdown string.
+
+    Parameters
+    ----------
+    card : BattleCard
+        The card instance to render.
+
+    Returns
+    -------
+    str
+        Complete Markdown string for the card.
+    """
+    lines: list[str] = []
+
+    # Header
+    lines.append(f"# Card {card.card_number}: {card.title}")
+    lines.append("")
+
+    # Summary blockquote
+    lines.append(f"> {card.summary}")
+    lines.append("")
+
+    # Fact section
+    lines.append("## Fact")
+    lines.append("")
+    for bullet in card.fact.content:
+        lines.append(f"- {bullet}")
+    lines.append("")
+
+    # Chart reference (if any)
+    if card.fact.chart_reference:
+        chart_filename = card.fact.chart_reference.split("/")[-1]
+        lines.append(f"![]({chart_filename})")
+        lines.append("")
+
+    # Impact section
+    lines.append("## Impact")
+    lines.append("")
+    for bullet in card.impact.content:
+        lines.append(f"- {bullet}")
+    lines.append("")
+
+    # Act section
+    lines.append("## Act")
+    lines.append("")
+    for bullet in card.act.content:
+        lines.append(f"- {bullet}")
+    lines.append("")
+
+    # Footer
+    lines.append("---")
+    lines.append("")
+    sources_str = ", ".join(card.sources)
+    lines.append(f"*Last updated: {card.last_updated} | Sources: {sources_str}*")
+    lines.append("")
+
+    return "\n".join(lines)
diff --git a/src/battlecards/claim_extractor.py b/src/battlecards/claim_extractor.py
new file mode 100644
index 0000000..3f7a080
--- /dev/null
+++ b/src/battlecards/claim_extractor.py
@@ -0,0 +1,222 @@
+"""Claim extraction module for battle card generation.
+
+Parses narrative documents and data modules to extract
+claim/evidence/implication triples suitable for FIA card assembly.
+"""
+
+from __future__ import annotations
+
+import re
+from pathlib import Path
+from typing import Optional
+
+
+class ClaimExtractor:
+    """Extract quantified claims from narratives and data modules.
+
+    Methods
+    -------
+    extract_from_narrative(narrative_path: str) -> list[dict]
+        Parse a narrative Markdown file for claim triples.
+    extract_from_data(data_module_path: str) -> list[dict]
+        Extract quantified claims from a Python data module.
+    map_to_cards(claims: list[dict]) -> dict
+        Map extracted claims to card numbers (1-8).
+
+    Claim dict format
+    -----------------
+    {
+        "card_number": int,
+        "section": "fact" | "impact" | "act",
+        "claim": str,
+        "evidence": str,
+        "source": str,
+    }
+    """
+
+    # Card number to topic mapping for heuristic assignment
+    _CARD_TOPICS = {
+        1: ("valuation", "cape", "market cap", "shiller", "p/e"),
+        2: ("infrastructure", "data center", "hyperscaler", "capex"),
+        3: ("gpu", "utilization", "tensor", "compute"),
+        4: ("startup", "funding", "venture", "valuation disconnect"),
+        5: ("enterprise", "deployment", "adoption", "production"),
+        6: ("developer", "coding", "programming", "ide"),
+        7: ("quality", "security", "vulnerability", "bug"),
+        8: ("productivity", "long-term", "trajectory", "efficiency"),
+    }
+
+    def extract_from_narrative(
+        self, narrative_path: str
+    ) -> list[dict]:
+        """Parse a Markdown narrative for claim/evidence/implication triples.
+
+        Parameters
+        ----------
+        narrative_path : str
+            Path to the Markdown narrative file.
+
+        Returns
+        -------
+        list[dict]
+            List of extracted claim dicts.
+        """
+        claims: list[dict] = []
+        path = Path(narrative_path)
+
+        if not path.exists():
+            return claims
+
+        text = path.read_text(encoding="utf-8")
+
+        # Pattern: bullet points that contain quantitative data
+        # Matches lines starting with "- " that contain numbers
+        bullet_pattern = re.compile(
+            r"^[-*]\s+(.+?[\d%]+\S.*?)$",
+            re.MULTILINE,
+        )
+
+        for match in bullet_pattern.finditer(text):
+            bullet_text = match.group(1).strip()
+
+            # Extract evidence (numeric data points)
+            numbers = re.findall(
+                r"\d+(?:,\d{3})*(?:\.\d+)?[%$]?",
+                bullet_text,
+            )
+            evidence = ", ".join(numbers) if numbers else "qualitative"
+
+            # Determine section by context keywords
+            section = self._classify_section(bullet_text)
+
+            # Map to card number by topic
+            card_number = self._match_topic(bullet_text)
+
+            claim = {
+                "card_number": card_number,
+                "section": section,
+                "claim": bullet_text,
+                "evidence": evidence,
+                "source": "case_narrative",
+            }
+            claims.append(claim)
+
+        return claims
+
+    def extract_from_data(
+        self, data_module_path: str
+    ) -> list[dict]:
+        """Extract quantified claims from a Python data module.
+
+        Reads module-level list[dict] or dict constants and
+        extracts notable data points as claims.
+
+        Parameters
+        ----------
+        data_module_path : str
+            Path to the Python data module file.
+
+        Returns
+        -------
+        list[dict]
+            List of extracted claim dicts.
+        """
+        claims: list[dict] = []
+        path = Path(data_module_path)
+
+        if not path.exists():
+            return claims
+
+        text = path.read_text(encoding="utf-8")
+
+        # Extract module-level variable names (list[dict] or dict)
+        var_pattern = re.compile(
+            r"^(\w+):\s*list\[dict\].*?=(\[.*?\])",
+            re.MULTILINE | re.DOTALL,
+        )
+
+        module_name = path.stem
+
+        for match in var_pattern.finditer(text):
+            var_name = match.group(1)
+            data_str = match.group(2)
+
+            # Extract representative values from the data
+            numbers = re.findall(
+                r"[\d]+(?:,[\d]{3})*(?:\.[\d]+)?",
+                data_str,
+            )
+
+            if numbers:
+                # Take first and last significant values
+                sample = f"Range: {numbers[0]} to {numbers[-1]}"
+                card_number = self._match_topic(var_name)
+
+                claim = {
+                    "card_number": card_number,
+                    "section": "fact",
+                    "claim": f"{var_name}: {sample}",
+                    "evidence": sample,
+                    "source": module_name,
+                }
+                claims.append(claim)
+
+        return claims
+
+    def map_to_cards(self, claims: list[dict]) -> dict:
+        """Map a list of claims to card numbers (1-8).
+
+        Parameters
+        ----------
+        claims : list[dict]
+            List of claim dicts to organize.
+
+        Returns
+        -------
+        dict
+            Mapping of card_number -> list of claims for that card.
+        """
+        card_map: dict[int, list[dict]] = {i: [] for i in range(1, 9)}
+
+        for claim in claims:
+            card_num = claim.get("card_number", 1)
+            # Clamp to valid range
+            card_num = max(1, min(8, card_num))
+            card_map[card_num].append(claim)
+
+        return card_map
+
+    # -----------------------------------------------------------------------
+    # Private helpers
+    # -----------------------------------------------------------------------
+
+    @staticmethod
+    def _classify_section(text: str) -> str:
+        """Classify a text snippet into fact, impact, or act section."""
+        lower = text.lower()
+        if any(
+            kw in lower
+            for kw in [
+                "risk", "impact", "threat", "consequence", "could",
+                "would", "may lead", "potential",
+            ]
+        ):
+            return "impact"
+        if any(
+            kw in lower
+            for kw in [
+                "should", "recommend", "act", "take action",
+                "consider", "monitor", "hedge",
+            ]
+        ):
+            return "act"
+        return "fact"
+
+    @staticmethod
+    def _match_topic(text: str) -> int:
+        """Match text to the closest card number by topic keywords."""
+        lower = text.lower()
+        for card_num, keywords in ClaimExtractor._CARD_TOPICS.items():
+            if any(kw in lower for kw in keywords):
+                return card_num
+        return 1  # Default to card 1
diff --git a/src/battlecards/generate_deck.py b/src/battlecards/generate_deck.py
new file mode 100644
index 0000000..e1cffd3
--- /dev/null
+++ b/src/battlecards/generate_deck.py
@@ -0,0 +1,248 @@
+"""Deck assembly module for battle cards.
+
+Combines individual card Markdown files into a single,
+well-structured evidence deck with cover page, TOC, and source appendix.
+"""
+
+from __future__ import annotations
+
+from datetime import datetime, timezone
+from pathlib import Path
+
+from src.battlecards.card_templates import BattleCard, FIASection, render_card
+
+
+# ---------------------------------------------------------------------------
+# Card metadata for TOC generation
+# ---------------------------------------------------------------------------
+
+_CARD_METADATA = [
+    {
+        "number": 1,
+        "filename": "card_01_market_valuation.md",
+        "title": "Market Valuation Extremes",
+        "cluster": "bubble",
+    },
+    {
+        "number": 2,
+        "filename": "card_02_ai_infrastructure.md",
+        "title": "AI Infrastructure Buildout",
+        "cluster": "bubble",
+    },
+    {
+        "number": 3,
+        "filename": "card_03_gpu_utilization.md",
+        "title": "GPU Utilization Paradox",
+        "cluster": "bubble",
+    },
+    {
+        "number": 4,
+        "filename": "card_04_startup_valuations.md",
+        "title": "Startup Valuation Disconnect",
+        "cluster": "bubble",
+    },
+    {
+        "number": 5,
+        "filename": "card_05_enterprise_deployment.md",
+        "title": "Real-World Enterprise Deployment",
+        "cluster": "value",
+    },
+    {
+        "number": 6,
+        "filename": "card_06_developer_adoption.md",
+        "title": "Developer Adoption Reality",
+        "cluster": "value",
+    },
+    {
+        "number": 7,
+        "filename": "card_07_code_quality_caveats.md",
+        "title": "Code Quality and Security Caveats",
+        "cluster": "value",
+    },
+    {
+        "number": 8,
+        "filename": "card_08_long_term_productivity.md",
+        "title": "Long-Term Productivity Trajectory",
+        "cluster": "value",
+    },
+]
+
+
+class DeckGenerator:
+    """Assemble individual battle cards into a complete evidence deck.
+
+    Methods
+    -------
+    generate_deck(card_directory: str, output_path: str) -> str
+        Combine all card Markdown files into a single deck with
+        cover page, table of contents, and source appendix.
+    """
+
+    def generate_deck(
+        self, card_directory: str, output_path: str
+    ) -> str:
+        """Combine all card Markdown files into a single evidence deck.
+
+        Parameters
+        ----------
+        card_directory : str
+            Path to the directory containing card Markdown files.
+        output_path : str
+            Destination path for the assembled deck Markdown file.
+
+        Returns
+        -------
+        str
+            Absolute path to the generated deck file.
+        """
+        card_dir = Path(card_directory)
+        output_file = Path(output_path)
+        output_file.parent.mkdir(parents=True, exist_ok=True)
+
+        # Collect all sources
+        all_sources: set[str] = set()
+
+        lines: list[str] = []
+
+        # ---- Cover page ----
+        lines.append("# AI Bubble Battle Cards — Evidence Deck")
+        lines.append("")
+        lines.append("> Argument-ready, evidence-backed one-pagers for AI market analysis.")
+        now_str = datetime.now(timezone.utc).strftime("%Y-%m-%d")
+        lines.append(f"> Last updated: {now_str}")
+        lines.append("")
+
+        # ---- Table of Contents ----
+        lines.append("## Table of Contents")
+        lines.append("")
+        lines.append("### Cluster A: The Bubble Exists")
+        lines.append("")
+        for meta in _CARD_METADATA[:4]:
+            lines.append(
+                f"- [{meta['title']}](cards/{meta['filename']})"
+            )
+        lines.append("")
+        lines.append("### Cluster B: LLMs Are Still Valuable")
+        lines.append("")
+        for meta in _CARD_METADATA[4:]:
+            lines.append(
+                f"- [{meta['title']}](cards/{meta['filename']})"
+            )
+        lines.append("")
+        lines.append("---")
+        lines.append("")
+
+        # ---- Full card content ----
+        for meta in _CARD_METADATA:
+            card_file = card_dir / meta["filename"]
+            if card_file.exists():
+                card_content = card_file.read_text(encoding="utf-8")
+                lines.append(card_content)
+                lines.append("")
+                lines.append("---")
+                lines.append("")
+            else:
+                lines.append(f"*Card {meta['number']} ({meta['title']}) not found.*")
+                lines.append("")
+
+        # ---- Source Appendix ----
+        lines.append("## Source Appendix")
+        lines.append("")
+        lines.append("*Primary data sources referenced across all battle cards:*")
+        lines.append("")
+
+        # If we have collected sources, list them; otherwise provide defaults
+        if all_sources:
+            for source in sorted(all_sources):
+                lines.append(f"- {source}")
+        else:
+            lines.append("- Yale/Shiller CAPE data (multpl.com)")
+            lines.append("- FRED economic indicators")
+            lines.append("- World Bank debt & GDP datasets")
+            lines.append("- Industry research reports (2024–2026)")
+
+        lines.append("")
+
+        deck_content = "\n".join(lines)
+        output_file.write_text(deck_content, encoding="utf-8")
+
+        return str(output_file.resolve())
+
+    def generate_deck_from_cards(
+        self, cards: list[BattleCard], output_path: str
+    ) -> str:
+        """Generate a deck directly from BattleCard instances.
+
+        Parameters
+        ----------
+        cards : list[BattleCard]
+            List of BattleCard instances to include.
+        output_path : str
+            Destination path for the deck file.
+
+        Returns
+        -------
+        str
+            Absolute path to the generated deck file.
+        """
+        output_file = Path(output_path)
+        output_file.parent.mkdir(parents=True, exist_ok=True)
+
+        all_sources: set[str] = set()
+        for card in cards:
+            all_sources.update(card.sources)
+
+        lines: list[str] = []
+
+        # Cover page
+        lines.append("# AI Bubble Battle Cards — Evidence Deck")
+        lines.append("")
+        lines.append("> Argument-ready, evidence-backed one-pagers for AI market analysis.")
+        now_str = datetime.now(timezone.utc).strftime("%Y-%m-%d")
+        lines.append(f"> Last updated: {now_str}")
+        lines.append("")
+
+        # TOC
+        lines.append("## Table of Contents")
+        lines.append("")
+
+        bubble_cards = [c for c in cards if c.cluster == "bubble"]
+        value_cards = [c for c in cards if c.cluster == "value"]
+
+        if bubble_cards:
+            lines.append("### Cluster A: The Bubble Exists")
+            lines.append("")
+            for card in sorted(bubble_cards, key=lambda c: c.card_number):
+                safe_title = card.title.lower().replace(" ", "_")
+                lines.append(f"- [Card {card.card_number}: {card.title}]")
+            lines.append("")
+
+        if value_cards:
+            lines.append("### Cluster B: LLMs Are Still Valuable")
+            lines.append("")
+            for card in sorted(value_cards, key=lambda c: c.card_number):
+                lines.append(f"- [Card {card.card_number}: {card.title}]")
+            lines.append("")
+
+        lines.append("---")
+        lines.append("")
+
+        # Card content
+        for card in sorted(cards, key=lambda c: c.card_number):
+            rendered = render_card(card)
+            lines.append(rendered)
+            lines.append("")
+            lines.append("---")
+            lines.append("")
+
+        # Source appendix
+        lines.append("## Source Appendix")
+        lines.append("")
+        for source in sorted(all_sources):
+            lines.append(f"- {source}")
+        lines.append("")
+
+        deck_content = "\n".join(lines)
+        output_file.write_text(deck_content, encoding="utf-8")
+
+        return str(output_file.resolve())
diff --git a/src/battlecards/mini_charts.py b/src/battlecards/mini_charts.py
new file mode 100644
index 0000000..9d3600c
--- /dev/null
+++ b/src/battlecards/mini_charts.py
@@ -0,0 +1,287 @@
+"""Mini-chart engine for battle card visualizations.
+
+Generates compact, themed 5x3 inch charts suitable for embedding
+in FIA battle cards. Uses the existing project styling utilities.
+"""
+
+from __future__ import annotations
+
+import argparse
+import sys
+from pathlib import Path
+
+import matplotlib
+matplotlib.use("Agg")
+import matplotlib.figure  # noqa: E402
+import matplotlib.pyplot as plt  # noqa: E402
+
+from src.utils.styling import (  # noqa: E402
+    AI_SPEND,
+    BUBBLE_ZONE,
+    REVENUE,
+    GRAY_DARK,
+    WHITE,
+    EXPORT_DPI,
+    get_theme,
+    apply_theme,
+)
+
+# ---------------------------------------------------------------------------
+# Sizing constants
+# ---------------------------------------------------------------------------
+
+MINI_FIGURE_SIZE = (5, 3)  # width, height in inches
+MINI_DPI = 300
+
+MIN_LABEL_FONT_SIZE = 9
+MIN_ANNOTATION_FONT_SIZE = 11
+MIN_TITLE_FONT_SIZE = 13
+
+
+class MiniChartEngine:
+    """Engine for generating compact, themed mini-charts for battle cards.
+
+    Each method creates a 5x3 inch figure, applies the project theme,
+    draws the requested chart type, and saves as a PNG at 300 DPI.
+    """
+
+    def generate_line_trend(
+        self, data: list[dict], title: str, save_path: str
+    ) -> str:
+        """Generate a line trend mini-chart.
+
+        Parameters
+        ----------
+        data : list[dict]
+            Each dict should have 'x' and 'y' keys.
+        title : str
+            Chart title.
+        save_path : str
+            Output file path.
+
+        Returns
+        -------
+        str
+            Absolute path to the saved PNG file.
+        """
+        fig, ax = plt.subplots(figsize=MINI_FIGURE_SIZE)
+        apply_theme(fig, ax)
+
+        x_values = [d["x"] for d in data]
+        y_values = [d["y"] for d in data]
+
+        ax.plot(x_values, y_values, color=AI_SPEND, linewidth=1.5)
+        ax.set_title(title, fontsize=MIN_TITLE_FONT_SIZE, fontweight="bold")
+        ax.tick_params(axis="both", labelsize=MIN_LABEL_FONT_SIZE)
+        ax.set_xlabel("Time", fontsize=MIN_LABEL_FONT_SIZE)
+        ax.set_ylabel("Value", fontsize=MIN_LABEL_FONT_SIZE)
+
+        self._save(fig, save_path)
+        return save_path
+
+    def generate_horizontal_bar(
+        self, data: list[dict], title: str, save_path: str
+    ) -> str:
+        """Generate a horizontal bar mini-chart.
+
+        Parameters
+        ----------
+        data : list[dict]
+            Each dict should have 'label' and 'value' keys.
+        title : str
+            Chart title.
+        save_path : str
+            Output file path.
+
+        Returns
+        -------
+        str
+            Absolute path to the saved PNG file.
+        """
+        fig, ax = plt.subplots(figsize=MINI_FIGURE_SIZE)
+        apply_theme(fig, ax)
+
+        labels = [d["label"] for d in data]
+        values = [d["value"] for d in data]
+        colors = [
+            AI_SPEND, BUBBLE_ZONE, REVENUE, GRAY_DARK, WHITE
+        ] * (len(labels) // 5 + 1)
+
+        ax.barh(labels, values, color=colors[:len(labels)], height=0.6)
+        ax.set_title(title, fontsize=MIN_TITLE_FONT_SIZE, fontweight="bold")
+        ax.tick_params(axis="both", labelsize=MIN_LABEL_FONT_SIZE)
+
+        self._save(fig, save_path)
+        return save_path
+
+    def generate_utilization_bar(
+        self, data: list[dict], title: str, save_path: str
+    ) -> str:
+        """Generate a utilization bar chart (e.g. GPU utilization).
+
+        Parameters
+        ----------
+        data : list[dict]
+            Each dict should have 'label', 'value', and 'max_value' keys.
+        title : str
+            Chart title.
+        save_path : str
+            Output file path.
+
+        Returns
+        -------
+        str
+            Absolute path to the saved PNG file.
+        """
+        fig, ax = plt.subplots(figsize=MINI_FIGURE_SIZE)
+        apply_theme(fig, ax)
+
+        labels = [d["label"] for d in data]
+        values = [d["value"] for d in data]
+        max_values = [d.get("max_value", 100) for d in data]
+
+        # Background bars for max
+        ax.barh(labels, max_values, color="#ecf0f1", height=0.6)
+        # Foreground bars for actual utilization
+        colors = [
+            BUBBLE_ZONE if v / m < 0.3 else REVENUE
+            for v, m in zip(values, max_values)
+        ]
+        ax.barh(labels, values, color=colors, height=0.6)
+
+        ax.set_title(title, fontsize=MIN_TITLE_FONT_SIZE, fontweight="bold")
+        ax.tick_params(axis="both", labelsize=MIN_LABEL_FONT_SIZE)
+
+        self._save(fig, save_path)
+        return save_path
+
+    def generate_comparison_bar(
+        self, data: list[dict], title: str, save_path: str
+    ) -> str:
+        """Generate a grouped comparison bar chart.
+
+        Parameters
+        ----------
+        data : list[dict]
+            Each dict should have 'label' and multiple value keys
+            (e.g. 'value_a', 'value_b').
+        title : str
+            Chart title.
+        save_path : str
+            Output file path.
+
+        Returns
+        -------
+        str
+            Absolute path to the saved PNG file.
+        """
+        fig, ax = plt.subplots(figsize=MINI_FIGURE_SIZE)
+        apply_theme(fig, ax)
+
+        labels = [d["label"] for d in data]
+        keys = [k for k in data[0].keys() if k != "label"]
+
+        import numpy as np
+
+        x = np.arange(len(labels))
+        width = 0.35
+
+        for i, key in enumerate(keys):
+            values = [d.get(key, 0) for d in data]
+            color = AI_SPEND if i == 0 else REVENUE
+            ax.bar(x + i * width, values, width, label=key, color=color)
+
+        ax.set_title(title, fontsize=MIN_TITLE_FONT_SIZE, fontweight="bold")
+        ax.set_xticks(x + width / 2)
+        ax.set_xticklabels(labels, fontsize=MIN_LABEL_FONT_SIZE)
+        ax.tick_params(axis="y", labelsize=MIN_LABEL_FONT_SIZE)
+        ax.legend(fontsize=MIN_LABEL_FONT_SIZE)
+
+        self._save(fig, save_path)
+        return save_path
+
+    @staticmethod
+    def _save(fig: matplotlib.figure.Figure, save_path: str) -> None:
+        """Save a figure with tight layout at MINI_DPI."""
+        Path(save_path).parent.mkdir(parents=True, exist_ok=True)
+        fig.savefig(save_path, dpi=MINI_DPI, bbox_inches="tight")
+        plt.close(fig)
+
+
+# ---------------------------------------------------------------------------
+# CLI test entry point
+# ---------------------------------------------------------------------------
+
+def _run_tests() -> None:
+    """Generate 4 placeholder test charts to output/battlecards/charts/."""
+    base_dir = Path("output/battlecards/charts")
+    engine = MiniChartEngine()
+
+    # Test 1: Line trend
+    line_data = [
+        {"x": f"Q{i}", "y": 10 + i * 3} for i in range(1, 5)
+    ]
+    path1 = engine.generate_line_trend(
+        line_data,
+        "AI Spending Trend (Test)",
+        str(base_dir / "test_line_trend.png"),
+    )
+    print(f"  Line trend: {path1}")
+
+    # Test 2: Horizontal bar
+    bar_data = [
+        {"label": "Cloud A", "value": 85},
+        {"label": "Cloud B", "value": 62},
+        {"label": "On-prem", "value": 28},
+    ]
+    path2 = engine.generate_horizontal_bar(
+        bar_data,
+        "AI Infrastructure Spending (Test)",
+        str(base_dir / "test_horizontal_bar.png"),
+    )
+    print(f"  Horizontal bar: {path2}")
+
+    # Test 3: Utilization bar
+    util_data = [
+        {"label": "Company A", "value": 18, "max_value": 100},
+        {"label": "Company B", "value": 24, "max_value": 100},
+        {"label": "Company C", "value": 45, "max_value": 100},
+    ]
+    path3 = engine.generate_utilization_bar(
+        util_data,
+        "GPU Utilization (Test)",
+        str(base_dir / "test_utilization_bar.png"),
+    )
+    print(f"  Utilization bar: {path3}")
+
+    # Test 4: Comparison bar
+    comp_data = [
+        {"label": "2023", "value_a": 50, "value_b": 30},
+        {"label": "2024", "value_a": 75, "value_b": 45},
+        {"label": "2025", "value_a": 90, "value_b": 55},
+    ]
+    path4 = engine.generate_comparison_bar(
+        comp_data,
+        "Spend vs Revenue Comparison (Test)",
+        str(base_dir / "test_comparison_bar.png"),
+    )
+    print(f"  Comparison bar: {path4}")
+
+    print("All 4 test charts generated successfully.")
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(
+        description="Battle card mini-chart engine"
+    )
+    parser.add_argument(
+        "--test",
+        action="store_true",
+        help="Generate 4 placeholder test charts",
+    )
+    args = parser.parse_args()
+
+    if args.test:
+        _run_tests()
+    else:
+        parser.print_help()