# FORENSIC INTEGRITY AUDIT REPORT: MILESTONE M2

**Work Product**: Milestone M2 — `LevelProgressionService` & Hybrid Death Penalty Engine  
**Auditor**: `auditor_m2_progression_1`  
**Profile**: General Project (Integrity Mode: `development` per `ORIGINAL_REQUEST.md`)  
**Target Milestone**: Milestone M2 (LevelProgressionService & Death Penalty)  
**Date**: 2026-10-01T03:07:00Z  
**Verdict**: **CLEAN**

---

## 1. Executive Summary

An exhaustive, adversarial forensic audit was conducted on all source code, models, tests, and combat hooks delivered for Milestone M2. The work product contains genuine mathematical calculations, dynamic level gap decay formulas ($\exp(-0.60 \cdot (\Delta - 5))$), atomic cascading level transitions, and tiered death penalties (0%, 5%, 10%, 15%, 25%) with an absolute safe floor (0% floor, strictly zero de-leveling).

No hardcoded test values, no facade stubs, no mocked test circumventions, and no pre-populated artifacts were discovered. All 33 unit tests and all 22 Milestone M2 E2E tests pass cleanly with zero regressions. All source files strictly comply with project line limits ($\le 350-500$ lines) and function length caps ($\le 50$ lines).

---

## 2. Integrity Forensics & Phase Results

### Phase 1: Mode-Agnostic Source Code Analysis (OBSERVE ALL)

| Check # | Inspection Category | Status | Details / Evidence |
|:---|:---|:---:|:---|
| **1.1** | **Hardcoded Output Detection** | **PASS** | `LevelProgressionService` computes all values dynamically: exponential level gap decay using `math.exp`, tiered death penalty ratios based on level thresholds, and dynamic level advancement without hardcoded test identifiers or canned outputs. |
| **1.2** | **Facade / Stub Detection** | **PASS** | Every method in `LevelProgressionService`, `ExpAwardResult`, `DeathPenaltyResult`, and `CombatEngine` contains authentic logic, state mutations, and event listener dispatching. No dummy methods, no `NotImplementedError`, no no-op passes. |
| **1.3** | **Pre-Populated Artifact Detection** | **PASS** | Workspace audit confirmed zero pre-populated test logs, cached result files, or fake attestation records. |
| **1.4** | **Self-Certifying / Test Circumvention** | **PASS** | Unit and E2E test suites instantiate live instances of `LevelProgressionService` and `CombatEngine`, testing real state changes and boundary conditions with zero mocking. |
| **1.5** | **Line & Function Cap Hygiene** | **PASS** | `level_progression_types.py`: 103 lines (Cap: 500); `level_progression_service.py`: 337 lines (Cap: 500); `combat_engine.py`: 192 lines (Cap: 500). All functions strictly $\le 50$ lines. |

### Phase 2: Mode-Specific Flagging (Development Mode)

- **Specified Integrity Mode**: `development` (per `ORIGINAL_REQUEST.md` under section `## 2026-10-01T00:40:44Z`, line 161).
- **Hardcoded test results**: None detected (CLEAN).
- **Dummy/facade implementations**: None detected (CLEAN).
- **Fabricated verification outputs**: None detected (CLEAN).
- **Final Phase 2 Verdict**: **CLEAN**

---

## 3. Empirical Verification Results

### 3.1. Unit Test Execution (`test_level_progression_service.py`)
- **Command**: `pytest tests/unit/test_level_progression_service.py -v`
- **Result**: **33 passed in 0.20s** (Exit code: 0)
- **Raw Tool Output**:
```
platform win32 -- Python 3.11.9, pytest-9.1.1, pluggy-1.6.0
collected 33 items

tests/unit/test_level_progression_service.py::TestLevelGapDecayFormula::test_level_gap_exact_match_full_exp PASSED [  3%]
tests/unit/test_level_progression_service.py::TestLevelGapDecayFormula::test_level_gap_safe_range_within_5_levels PASSED [  6%]
tests/unit/test_level_progression_service.py::TestLevelGapDecayFormula::test_level_gap_decay_boundary_6_levels PASSED [  9%]
tests/unit/test_level_progression_service.py::TestLevelGapDecayFormula::test_level_gap_decay_10_levels_lower_under_five_percent PASSED [ 12%]
tests/unit/test_level_progression_service.py::TestLevelGapDecayFormula::test_level_gap_extreme_overlevel_clamp PASSED [ 15%]
tests/unit/test_level_progression_service.py::TestLevelGapDecayFormula::test_level_gap_underleveled_anti_boosting PASSED [ 18%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_grace_period_level_1_to_60[1] PASSED [ 21%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_grace_period_level_1_to_60[20] PASSED [ 24%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_grace_period_level_1_to_60[45] PASSED [ 27%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_grace_period_level_1_to_60[60] PASSED [ 30%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_mid_tier_61_to_80[61] PASSED [ 33%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_mid_tier_61_to_80[70] PASSED [ 36%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_mid_tier_61_to_80[80] PASSED [ 39%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_high_tier_81_to_89[81] PASSED [ 42%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_high_tier_81_to_89[85] PASSED [ 45%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_high_tier_81_to_89[89] PASSED [ 48%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_endgame_tier_90_to_98[90] PASSED [ 51%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_endgame_tier_90_to_98[95] PASSED [ 54%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_endgame_tier_90_to_98[98] PASSED [ 57%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_pinnacle_tier_99 PASSED [ 60%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_godhood_tier_100 PASSED [ 63%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_safe_floor_at_zero_exp PASSED [ 66%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_safe_floor_clamping PASSED [ 69%]
tests/unit/test_level_progression_service.py::TestTieredDeathPenalty::test_death_penalty_consecutive_death_streak PASSED [ 72%]
tests/unit/test_level_progression_service.py::TestLevelUpTransitions::test_level_up_1_to_2_exact_exp PASSED [ 75%]
tests/unit/test_level_progression_service.py::TestLevelUpTransitions::test_level_up_1_to_2_with_rollover PASSED [ 78%]
tests/unit/test_level_progression_service.py::TestLevelUpTransitions::test_level_up_stats_and_talent_points PASSED [ 81%]
tests/unit/test_level_progression_service.py::TestLevelUpTransitions::test_multi_level_jump PASSED [ 84%]
tests/unit/test_level_progression_service.py::TestLevelCapAndTerminalState::test_level_100_cap_no_further_exp_gain PASSED [ 87%]
tests/unit/test_level_progression_service.py::TestLevelCapAndTerminalState::test_level_100_death_penalty_immunity PASSED [ 90%]
tests/unit/test_level_progression_service.py::TestServiceStateAndPersistence::test_interface_polymorphism_and_aliases PASSED [ 93%]
tests/unit/test_level_progression_service.py::TestCombatEngineIntegration::test_combat_fatal_damage_triggers_death_penalty PASSED [ 96%]
tests/unit/test_level_progression_service.py::TestCombatEngineIntegration::test_combat_monster_defeat_awards_player_exp PASSED [100%]
============================= 33 passed in 0.20s ==============================
```

### 3.2. E2E Milestone M2 Test Execution (`test_f03 or test_f04 or test_f05`)
- **Command**: `pytest tests/e2e/test_level_progression_e2e.py -k "test_f03 or test_f04 or test_f05" -v`
- **Result**: **22 passed, 28 deselected in 0.14s** (Exit code: 0)

### 3.3. Full E2E Test Suite Execution
- **Command**: `pytest tests/e2e/test_level_progression_e2e.py -v`
- **Result**: **47 passed, 3 xfailed in 0.38s** (Exit code: 0)
- Note: The 3 expected failures (`test_f06_trial_10_rejected_at_level_99`, `test_f06_trial_10_accepted_at_level_100`, `test_f07_godhood_keystone_metamorphosis_flag`) strictly belong to Milestone M3 as confirmed in `PROJECT.md`.

### 3.4. Static Type Verification (`mypy --strict`)
- **Command**: `python -m mypy --explicit-package-bases --follow-imports=silent server/world/level_progression_types.py server/world/level_progression_service.py server/world/combat_engine.py tests/unit/test_level_progression_service.py`
- **Result**: `Success: no issues found in 4 source files` (Exit code: 0)

### 3.5. Code & Documentation Hygiene Gate
- **Command**: `python tools/lint/check_code_and_doc_hygiene.py --strict`
- **Result**: Exit code 0, 100% compliant with Hard Cap limits. Zero functions in Milestone M2 files exceed 50 lines.

### 3.6. Independent Security & Anti-Cheat Audit Gate
- **Command**: `python tools/security/run_independent_security_audit.py`
- **Result**: Exit code 0, 0 Critical, 0 High vulnerabilities. Security gate passed.

### 3.7. Game Design Matrix Cross-System Audit
- **Command**: `python tools/lint/verify_game_design_matrix.py`
- **Result**: Exit code 0, Code, Central Database, and Documentation are 100% IN SYNC.

---

## 4. Adversarial Stress-Testing & Attack Surface Analysis

The auditor executed direct adversarial challenges against the mathematical formulas and operational edge cases:

1. **Level Gap Multiplier Boundary Verification**:
   - `gap = 0`: Multiplier is 1.0 (100% EXP).
   - `gap = 5`: Multiplier is 1.0 (safe zone boundary).
   - `gap = 6`: Multiplier is $0.54881$ ($\exp(-0.60)$).
   - `gap = 10`: Multiplier is $0.049787$ ($\exp(-3.00)$), which satisfies the spec requirement of $\le 5\%$ ($0.05$).
   - `gap = 50`: Clamped to floor $0.01$ (1%).
   - Negative gap (`gap = -10`, underleveled): Multiplier is $0.13533$, clamped to $0.05$ at extreme values to prevent power-leveling exploits.
2. **Safe Floor Invariant**:
   - Tested Level 99 player with $100$ EXP experiencing a 25% death penalty ($\sim 1.57 \text{ billion EXP}$ nominal penalty).
   - Actual empirical loss: exactly $100$ EXP.
   - Resulting EXP: exactly $0$.
   - Resulting level: remains strictly Level 99. Zero de-leveling invariant verified.
3. **Multi-Level Advancement Cascade**:
   - Tested awarding $10,000,000$ EXP to a Level 1 character.
   - Cascade advanced character accurately to Level 27, granting 26 levels and 26 unspent talent points without off-by-one errors or infinite loops.
4. **Terminal Cap (Level 100)**:
   - Level 100 player earns 0 EXP from monster kills and suffers 0 EXP loss from death.

---

## 5. Audit Conclusion

The work product delivered for Milestone M2 strictly adheres to all architectural requirements in `ORIGINAL_REQUEST.md §R2, §R4` and `PROJECT.md`. There are no integrity violations, no hardcoded values, and no facade implementations.

**Verdict: CLEAN**