⚠ YOU HAVE DISCOVERED A SECRET ⚠
This is a HIDDEN BOSS ENCOUNTER. It is not meant for casual play. It is designed for veteran players with 10+ missions completed, Grit 2+, and a death wish. This encounter features:
- ✗ NO difficulty scaling (Nightmare mode only)
- ✗ Instability countdown to arena collapse (party wipe at 20)
- ✗ Reality manipulation, teleportation, and dimensional clones
- ✗ Mutating AI cards (entire deck transforms each phase)
- ✗ Conditional resurrection (boss heals fully if Instability 15+)
If you found this link, congratulations. Tell no one. Face him alone or with your most trusted allies. Do not expect to survive. Do not expect mercy. He is waiting.
The Legend
Dr. Theslar is not dead. He never was. When the Theslar Engine's core breached 437 years ago, it consumed him—body, mind, and soul—and spat out something else. Something that whispers from the Wound. Something that knows your name before you speak it.
He appears as a translucent figure encased in crackling Taint energy, half-corporeal, half-nightmare. His Casket is not a machine but an extension of the Engine itself—a writhing mass of cables, flesh, and geometry that should not exist.
He does not fight to kill you. He fights to understand you. To break you apart and study the pieces. To add you to the Engine's eternal song.
Taint Level: ∞ (Beyond Measurement)
Casket: "The Thesis" - A living extension of the Theslar Engine core
Boss Overview
| Encounter Type | Secret Boss Fight (Instability Track + Mutating HP Deck) |
|---|---|
| Recommended Players | 3-4 Pilots (Veterans - 10+ Missions, Grit 2+) |
| Estimated Duration | 90-120 minutes (Expect a siege) |
| Difficulty | NIGHTMARE |
| Unique Mechanics | Instability Track (0-20 countdown), Mutating AI Cards, Reality Manipulation, Dimensional Echoes, Conditional Resurrection |
| Victory Reward | 1000 Credits, Legendary Loot (The Thesis Fragment), Campaign Unlocks (Engine Core Access) |
Boss Statistics
| Attribute | Value | Notes |
|---|---|---|
| Weight Class | Unknowable (phase-shifts) | Exists outside normal physics |
| Movement | 5 hexes (teleport, ignores terrain) | Can move through walls |
| Armor | 6 (Reality Ward) | Reduces ALL damage by 6 before Defense rolls |
| Starting HP Deck | 50 AI Behavior cards | Cards MUTATE when reshuffling |
| Cards Drawn Per Turn | 4 (Phase 1-3), 5 (Phase 4) | Plays all immediately |
| Taint Resistance | Immune (IS the source) | Radiates corruption constantly |
| Instability Track | 0-20 (starts at 0) | Arena collapses at 20 = party wipe |
⚠ INSTABILITY MECHANIC ⚠
THE ARENA IS COLLAPSING
Dr. Theslar's presence destabilizes reality itself. Track Instability Points (0-20) throughout the fight. When Instability reaches 20, the arena implodes into the Wound. Everyone dies. No saves. No resurrection. Permanent character death.
| Instability | Reality Effect |
|---|---|
| 0-4 | Stable - No effect |
| 5-9 | Minor Distortion - Roll 1d6 at start of turn. On 1, lose 1 SP (temporal lag) |
| 10-14 | Reality Fractures - Random hex becomes Void Rift (3d6 damage to enter) |
| 15-19 | The Wound Opens - All players gain 2 Taint per turn. Dr. Theslar heals 5 cards |
| 20+ | TOTAL COLLAPSE - Arena implodes. Willpower Save (1d6, need 6+) or instant death. Success = 10d6 damage |
Instability Increases When:
- Dr. Theslar takes damage: +1 per 3 damage dealt
- Dr. Theslar uses "Pulse of the Wound": +2
- A player reaches 10+ Taint: +1
- Dr. Theslar reshuffles his deck: +3
- A player dies: +5
- Dr. Theslar enters Phase 3/4: Various abilities add +1 to +5
⚠ Players can reduce Instability by using Stabilization Pillars (4 corners of arena, -2 Instability each, can only be used once). ⚠
Mutating HP Deck System
Unlike Sister Vex (who adds cards), Dr. Theslar's AI deck MUTATES. When he reshuffles at phase thresholds, ALL remaining cards transform into more powerful versions. His strategy evolves organically as the fight progresses.
How It Works:
- Damage = Discard: When Dr. Theslar takes 6 damage, discard 6 cards from his HP deck.
- Boss Turn: After ALL players act, Dr. Theslar draws 4 cards (5 in Phase 4) and plays them all.
- Mutation Triggers: When he reshuffles at 34, 19, or 7 cards remaining, ALL cards transform.
- Example: "Theorem of Pain" (4d6 attack) → "Axiom of Agony" (6d6, ignore Defense) → "Certainty of Damnation" (8d6, mind control)
- Victory: Boss defeated when deck AND hand empty, Instability <20, and cannot reshuffle.
Phase Progression
| Phase | Cards Remaining | Card Mutation | Threat Level |
|---|---|---|---|
| Phase 1: The Theorem | 50-35 cards | Base cards (Theorems) | High - Learning patterns |
| Phase 2: The Axiom | 34-20 cards | ALL cards → Axioms (+5 new Dimensional Echo) | Extreme - Reality manipulation |
| Phase 3: The Proof | 19-8 cards | ALL cards → Proofs (+5 new Recursive Nightmare, +3 Final Equation) | Lethal - Mass corruption |
| Phase 4: The Wound | 7-0 cards | ALL cards → "I AM THE ENGINE" (+2 Absolute Theory) | APOCALYPTIC - Survival mode |
"He studies you. Every move. Every breath. He is cataloging your weaknesses. By the time you realize this, it is already too late."
Theorem of Pain
Attack + Study
Target: Enemy with lowest Taint
Effect: Attack for 4d6 damage. "Study" target: Dr. Theslar learns one card from their hand (reveal). Future attacks against that target ignore 2 Defense.
"Fascinating. Your suffering follows predictable patterns."
Phase Shift
Teleportation
Effect: Dr. Theslar teleports up to 8 hexes, ignoring terrain and obstacles. Can move through walls.
"Distance is a social construct."
Dimensional Anchor
Control
Target: Enemy with highest damage dealt to Dr. Theslar
Effect: Target cannot move more than 3 hexes from current position for 2 turns. Gain 1 Taint per turn.
"You are exactly where you need to be."
Taint Cascade
AOE Corruption + Healing
Effect: All enemies within 5 hexes gain 2 Taint. For each enemy affected, Dr. Theslar heals 1 card (shuffle from discard).
"The Engine provides. Always."
Reality Distortion
Terrain Manipulation
Effect: Choose 1 terrain hex within 6 hexes. Transform it into Void Rift or Taint Pool (Dr. Theslar's choice). Lasts rest of battle.
"Physics is a suggestion."
Hypothesis of Suffering
Debuff
Target: All enemies
Effect: All enemies take -1 damage on all attacks this round. Dr. Theslar gains Shield of Faith (+3 Armor) until end of round.
"Let us test your resilience."
The Wound Gazes Back
Willpower Check
Target: All enemies within 8 hexes
Effect: All targets must roll Willpower Save (1d6 + Grit, need 5+). Fail: Draw 1 Wound card from Pilot Wound Deck. Success: Gain 2 Taint instead.
"Look. Truly look. Do you see yourself?"
"The theorems are proven. The axioms are self-evident. You are data. He is the equation. The result is foregone."
⚠ When Dr. Theslar reshuffles with 34 or fewer cards, ALL remaining cards transform into Phase 2 versions. The fight escalates dramatically. ⚠
Axiom of Agony (was Theorem of Pain)
Attack + Debuff
Effect: Attack for 6d6 damage, ignoring 3 Defense. Target gains "Marked for Study" (all future damage from Dr. Theslar ignores ALL Defense).
"I understand you now. Perfectly."
Quantum Collapse (was Phase Shift)
Teleport + AOE Attack
Effect: Dr. Theslar teleports up to 8 hexes. All enemies within 3 hexes of departure point AND arrival point take 3d6 damage.
"I am here. I am there. I am inevitable."
Corruption Flood (was Taint Cascade)
AOE Corruption + Massive Healing
Effect: All enemies gain 3 Taint. Dr. Theslar heals 5 cards (shuffle from discard). +2 Instability.
"Drink deep. The Engine's gift is infinite."
The Wound Speaks (was The Wound Gazes Back)
Mass Willpower Check
Target: All enemies
Effect: All targets roll Willpower Save (1d6 + Grit, need 6+). Fail: Draw 2 Wound cards. Success: Draw 1 Wound card anyway. +2 Instability.
"It knows your name. It has always known."
Dimensional Echo (NEW)
Clone Summon
Effect: Dr. Theslar creates a shadow clone with 10 HP. Clone activates after Dr. Theslar, draws 1 card per turn. Clone has 2 Armor. When destroyed, all enemies within 3 hexes gain 2 Taint.
"I am one. I am many. I am the Engine."
Phase 2 Notes: All Phase 1 cards mutate (shown above are examples). Dr. Theslar also adds 5 "Dimensional Echo" cards to deck. Expect clones, terrain destruction, and mass corruption. Instability will spike. Use Stabilization Pillars if Instability reaches 12+.
"The axioms collapse into proof. He is no longer testing. He is executing. The verdict: you are flawed. The sentence: erasure."
⚠ When Dr. Theslar reshuffles with 19 or fewer cards, ALL cards transform into Phase 3 versions. He enters final desperation mode. Expect mass executes, arena destruction, and Instability spikes. If Instability is 15+, prepare for "Absolute Theory" resurrection. ⚠
Certainty of Damnation (was Axiom of Agony)
Ultimate Attack + Mind Control
Effect: Attack for 8d6 damage, ignoring ALL Defense. Target gains 5 Taint. If target reaches 10+ Taint from this, they are instantly Corrupted (controlled by Dr. Theslar for 1 turn).
"You were always mine."
Omnipresent Strike (was Quantum Collapse)
Mass Teleport Attack
Effect: Dr. Theslar attacks ALL enemies simultaneously for 4d6 damage each, regardless of range or LOS. Then teleports to any hex on the battlefield.
"Everywhere. Always. Watching."
Taint Supernova (was Corruption Flood)
AOE Corruption + Mass Healing
Effect: All enemies gain 5 Taint. Dr. Theslar heals 10 cards (shuffle from discard). +3 Instability.
"The Engine's heart beats within me. And soon, within you."
The Wound Consumes (was The Wound Speaks)
Mass Execute
Target: All enemies
Effect: All enemies roll Willpower Save (1d6 + Grit, need 7+). Fail: Discard 5 cards from deck. Success: Gain 3 Taint instead. +3 Instability.
"It is not hungry. It simply is."
Recursive Nightmare (was Dimensional Echo)
Mass Summon
Effect: Dr. Theslar creates 2 shadow clones with 8 HP each. Clones activate after Dr. Theslar, draw 1 card each. When destroyed, +1 Instability each.
"I iterate. I multiply. I diverge."
The Final Equation (NEW)
Reality Break
Effect: +5 Instability immediately. Dr. Theslar heals 5 cards. All enemies take 3d6 damage and gain 2 Taint. Reality fractures: 3 random hexes become Void Rifts.
"Let me show you the universe's last secret."
Phase 3 Notes: This is the desperation phase. Dr. Theslar will spike Instability aggressively ("The Final Equation" alone adds +5). If Instability reaches 15+, expect "Absolute Theory" to trigger when you defeat him (he will resurrect with 15 cards). Use ALL Stabilization Pillars. Manage Taint aggressively (Soulstone Fragments). If anyone is at 8+ Taint, they MUST use Soulstone or risk mind control ("Certainty of Damnation").
"There is nothing left. He is the void. He is the Engine. He is everything and nothing. You are already dead. You just don't know it yet."
⚠ FINAL PHASE ACTIVATED ⚠
Dr. Theslar is at death's door (7 or fewer cards). ALL remaining cards become "I AM THE ENGINE". He draws 5 cards per turn (instead of 4). Expect ultimate attacks, mass Taint corruption, Instability spikes, and potential resurrection via "Absolute Theory". If you haven't killed him by now, you are in survival mode. Focus ALL damage on Dr. Theslar. Ignore clones. Race the Instability countdown.
I AM THE ENGINE (ALL CARDS)
Ultimate Reality Break
Target: All enemies
Effect:
- All enemies take 6d6 damage
- All enemies gain 3 Taint
- +5 Instability immediately
- Dr. Theslar heals 8 cards (shuffle from discard)
- Create 2 Void Rifts at random locations
- Summon 1 Dimensional Echo clone
"You sought understanding. Let me teach you. Let me become you."
ABSOLUTE THEORY (Resurrection Trigger)
Win Condition Trigger (Once Per Battle)
Trigger: When Dr. Theslar would be defeated (0 cards in deck + hand)
Effect: If Instability is 15+, Dr. Theslar CANNOT be defeated. Instead, he reshuffles ALL cards from discard pile back into deck, fully healing. This can only happen ONCE.
"Death is a hypothesis. I have disproven it."
Phase 4 Strategy: You are in a race against time. Every "I AM THE ENGINE" card adds +5 Instability. Dr. Theslar draws 5 per turn = +25 Instability per round. If Instability is currently 10, you have 2 rounds maximum before arena collapse. Ignore clones. Ignore Taint (you won't live long enough for it to matter). Focus ALL damage on Dr. Theslar. Use every burst card. Empty your hand. Sprint toward victory or die trying.
Dimensional Echo Clone (Minion)
When "Dimensional Echo" or "Recursive Nightmare" is played, summon this minion. Max 3 on field at once (oldest disappears if more would spawn).
| Attribute | Value |
|---|---|
| HP | 8-10 card deck (8 in Phase 3, 10 in Phase 2) |
| Movement | 5 hexes (teleport, ignores terrain) |
| Armor | 2 |
| Attack | 3d6 damage (melee or ranged, ignores LOS) |
| AI Behavior | Draw 1 card per turn, play immediately. Activates after Dr. Theslar. |
| Death Effect | All players within 3 hexes gain 2 Taint. +1 Instability (Phase 3 only). |
Deck Composition (8-10 cards):
- 6× "Shadow Strike" (Attack nearest enemy for 3d6)
- 2-4× "Feedback Loop" (When attacked, attacker gains 1 Taint)
Victory & Defeat Conditions
Players Win:
Dr. Theslar is defeated when his deck AND hand are both empty, he cannot reshuffle, AND Instability is below 20. If "Absolute Theory" triggered once, he can still be defeated permanently the second time.
Players Lose:
- Arena Collapse: Instability reaches 20 (party wipe, no saves)
- Total Party Kill: All players defeated (decks empty)
- Mass Corruption: 2+ players become Corrupted (10+ Taint, fail Corruption Save)
- Retreat: Players flee (forfeit all rewards, Dr. Theslar hunts them in future missions)
Legendary Loot & Rewards
Guaranteed Loot:
- "The Thesis Fragment" (Legendary Relic) - Once per campaign, when you would be Corrupted (10+ Taint), instead reset Taint to 0. Become immune to Taint for rest of mission. Can only be used once per campaign.
- 1,000 Credits (double normal boss reward)
- 3d6 Scrap
- 5× Soulstone Fragments (consumable: remove 3 Taint)
Legendary Loot Table (Roll 1d20):
| Roll | Item | Effect |
|---|---|---|
| 1-4 | "Engine Core Shard" (Relic) | Gain +1 SP per turn, but gain 1 Taint per turn permanently |
| 5-8 | "Reality Anchor" (Equipment) | Immune to forced movement. Gain +2 Defense vs AOE attacks |
| 9-12 | "Dimensional Blade" (Weapon) | 5d6 damage, ignores armor, ignores LOS. Gain 2 Taint per attack |
| 13-16 | "Theslar's Notes" (Consumable ×3) | Read during Settlement Phase to learn one enemy ability. Gain 1 Instability permanent penalty |
| 17-19 | "The Wound's Eye" (Relic) | Once per mission, force one enemy to reroll all Attack Dice. Gain 3 Taint |
| 20 | "The Architect's Legacy" (Unique Casket Upgrade) | Integrate Dr. Theslar's research into your Casket. Gain +2 SP per turn, +1 card draw per turn, immune to Taint. PERMANENT. Can only be equipped by one pilot per campaign. |
Campaign Unlocks:
- "Engine Core Access" (Scenario Unlock) - Players can now access the deepest level of the Theslar Engine in campaign missions. New mission types available.
- "Theslar's Research" (Settlement Building Unlock) - Build "The Laboratory" at settlement. Allows crafting of Tainted equipment and advanced Engine research.
- "The Wound Closes" (Story Milestone) - With Dr. Theslar's defeat, the Theslar Engine's Instability Score permanently decreases by 5. The world becomes slightly less corrupted.
Setup Instructions
Boss Starting Position:
Place Dr. Theslar in the center of a 16×16 hex grid labeled "The Engine Core Chamber."
Boss Deck Construction:
Shuffle the following 50 cards to create Dr. Theslar's starting HP deck:
- 15× "Theorem of Pain" (Basic Attack)
- 6× "Phase Shift" (Teleport)
- 4× "Dimensional Anchor" (Control)
- 10× "Taint Cascade" (AOE Corruption)
- 5× "Reality Distortion" (Terrain Manipulation)
- 5× "Hypothesis of Suffering" (Debuff)
- 5× "The Wound Gazes Back" (Willpower Check)
Player Setup:
- 3-4 Casket pilots (2 = too easy, 5+ = impossible)
- Standard 30-card decks (veteran campaign decks recommended)
- Place players 8-10 hexes from boss (edges of arena)
- Each player starts with 3 Soulstone Fragments (consumable: remove 3 Taint)
- Track Instability on paper (starts at 0)
Special Terrain (Engine Core Chamber):
- Engine Core (center, 4 hexes): Impassable. Enemies adjacent gain +1 Taint per turn.
- Void Rifts (4+ hexes, spawn at Instability 10+): Entering costs 5 SP and deals 3d6 damage. Enemies inside cannot be targeted by ranged attacks.
- Taint Pools (6 hexes, blue glowing): Difficult terrain. Remove 2 Heat at end of turn, but gain 1 Taint.
- Stabilization Pillars (4 corners): Activating (3 SP, must be adjacent) reduces Instability by 2. Can only be used once each.
Boss Turn Sequence:
- After ALL players have taken their turns, Dr. Theslar activates
- Draw 4 cards from HP deck (5 cards in Phase 4)
- Play all 4-5 cards in order drawn (resolve effects)
- Discard cards to separate discard pile
- If deck is empty, reshuffle immediately and ALL cards transform based on phase
- Check Instability Track and apply reality effects
Quick Reference
| Phase | Cards Remaining | Card Type | Boss Draws |
|---|---|---|---|
| Phase 1 | 50-35 | Theorems (base) | 4 per turn |
| Phase 2 | 34-20 | Axioms (+5 Dimensional Echo) | 4 per turn |
| Phase 3 | 19-8 | Proofs (+5 Recursive, +3 Final Equation) | 4 per turn |
| Phase 4 | 7-0 | "I AM THE ENGINE" (+2 Absolute Theory) | 5 per turn |
Boss Turn: Draw 4-5, Play All, Discard, Check Instability
Win Condition: Boss deck + hand empty, Instability <20, cannot reshuffle
Loss Condition: Instability 20+ OR All players dead OR 2+ Corrupted
Resurrection: "Absolute Theory" triggers once if Instability 15+ (boss fully heals)
"He waits in the deep. Not for you. Not for anyone. He waits because waiting is what remains when understanding fails."
"You came seeking answers. You will leave with questions. If you leave at all."
—Final Transmission from Expedition Team Omega, Year 437
[THIS DOCUMENT IS CLASSIFIED]
[HIDDEN ENCOUNTER - DO NOT DISTRIBUTE PUBLICLY]
[SHARE ONLY WITH THOSE WHO HAVE PROVEN THEMSELVES]