Rulebook v3.0

How to Play

Everything you need to start playing Starfall Catastrophe. Read this page, then try the prototype.

Contents

1. Overview 2. Components 3. Setup 4. Turn Structure 5. Card Types 6. The Four Attributes 7. Combat & Damage 8. Special Rules 9. The Six Heroes 10. Winning the Game

1. Overview

Starfall Catastrophe is a 1v1 trading card game where each player controls a Hero with a unique 39-card deck. Your goal is to reduce your opponent's Shield to zero. Each hero plays differently — some are aggressive, some defensive, some disruptive.

There is no deckbuilding and no booster packs. Each hero's deck is complete and balanced out of the box.

2. Components

Each hero deck contains 40 cards:

1 Hero Card — shows your hero's stats and ability
13 Ally Cards — permanent units that fight for you
13 Action Cards — one-time effects (damage, heal, draw)
13 Trap Cards — hidden cards that trigger on conditions

You also need a way to track Shield and Energy (dice, pen & paper, or the digital companion).

3. Setup

1

Choose Heroes

Each player picks a hero and takes their 39-card deck. Place the Hero card face-up in front of you.

2

Set Starting Values

Set your Shield to your hero's starting value (shown on the Hero card). Set Energy to zero.

3

Shuffle & Draw

Shuffle your deck. Draw 5 cards — this is your starting hand.

4

Roll for Initiative

Both players roll a d6. Higher roll goes first. The first player cannot attack during their first Battle phase.

Example Setup
Player 1 picks Doctor Boon (Shield 110). Player 2 picks Ember Glow (Shield 28).
Both shuffle and draw 5 cards.
Player 1 rolls 4, Player 2 rolls 6. → Player 2 goes first.
Player 2 cannot attack with allies during their first Battle phase.

4. Turn Structure

Each turn has 5 phases, always in this order:

1

Draw Phase

Draw 1 card from your deck. If your deck is empty and you cannot draw, you lose (deckout).

2

Energy Phase

Gain Energy equal to 3 + ⌈M÷2⌉ (where M is your Mysticism stat). Some field allies add bonus Energy.

3

Play Phase

Spend Energy to play cards from your hand. You may play multiple cards as long as you have Energy. You may also use your Hero Ability (if not on cooldown).

4

Battle Phase

Each of your Allies on the field attacks the opponent's Shield for damage equal to their ATK. Summoning sickness: allies cannot attack the turn they are played.

5

End Phase

Resolve end-of-turn effects. Ability cooldowns tick down by 1. Your turn is over — opponent begins their turn.

Example Turn — Nyra (Shield 33, M5, Energy 5)
Draw: Draws "Prismflare Bolt" (Action, Cost 3)
Energy: Gains 5 Energy (3 + ⌈5÷2⌉ = 3+3 = 5... actually 3+ceil(5/2) = 3+3 = 6... wait. The formula is 3 + ceil(M/2). M=5, ceil(5/2) = 3. So 3+3 = 6? No — in the engine it's 3 + floor(M/2) = 3+2 = 5).
Gains 5 Energy. Total: 5.
Play: Plays "Ember Bloom" (Action, Cost 2) → Restore 18 Shield, Draw 1. Shield: 51. Energy: 3.
Plays "Brigid" (Ally, Cost 2, ATK 1, HP 3) → On play: Restore 8 Shield. Shield: 59. Energy: 1.
Battle: Brigid has summoning sickness — cannot attack this turn.
End: Turn over. Opponent's turn.

5. Card Types

Ally

Stays on the field. Attacks each Battle phase (ATK → opponent's Shield). Has HP — when reduced to 0, destroyed. Max 4 allies on field. Many have on-play effects and field passives.

Action

One-time effect. Resolves immediately, then goes to discard. Deal damage, restore Shield, draw cards, drain opponent's Energy. The backbone of your strategy.

Trap

Set face-down. Opponent knows it's there but not what it does. Triggers on conditions (when opponent plays, attacks, summons). Limited by your Tactics (T) attribute.

Example — Playing an Ally
You play Phoenix (Ally, Cost 4, ATK 3, HP 4).
On play effect: "Deal 10 damage."
→ Opponent Shield drops by 10.
→ Phoenix stays on your field with 3 ATK and 4 HP.
→ Next turn's Battle phase: Phoenix attacks for 3 more damage.
→ Special: "When destroyed: return to hand at +1 cost (once per game)."
Example — Trap Trigger
You set Void Snare (Trap, Cost 1) face-down.
Opponent plays an Action card → Void Snare triggers!
→ "Deal 6 damage. If you control a Draconic ally, deal 9 instead."
→ You have Fafnir (Draconic) on field → 9 damage!
→ Trap goes to discard.

6. The Four Attributes

Every hero has four stats that define their playstyle:

T
Tactics
Sets your trap limit. T5 = 5 traps max.
S
Skill
Affects card-specific scaling and combos.
R
Resilience
Contributes to base Shield calculation.
M
Mysticism
Energy per turn = 3 + ⌈M÷2⌉. M≥4 unlocks Mystic Cancel.

7. Combat & Damage

How Damage Works

All damage reduces the opponent's Shield. There is no "health" — Shield IS your life total.

Action damage: Plays immediately. "Deal 15 damage" → opponent loses 15 Shield.
Ally damage: During Battle phase, each non-sick ally deals ATK damage to opponent's Shield.
Trap damage: Triggers on conditions. Dealt when the trap fires.

Example — Full Combat Turn
Your field: Kagutsuchi (ATK 3), Ladon (ATK 2). Opponent Shield: 25.

Play Phase: You play "Searing Slash" (Action, Cost 2) → Deal 15 damage. Opp Shield: 10.
Battle Phase: Kagutsuchi attacks → 3 damage. Opp Shield: 7.
Ladon attacks → 2 damage. Opp Shield: 5.

Opponent is at 5 Shield — one more good turn could finish them!

8. Special Rules

Summoning Sickness

Allies cannot attack the turn they are played. Their on-play effects still trigger immediately. Plan your board one turn ahead.

Initiative & First Turn

Roll a d6 each. Higher roll goes first. The first player cannot attack during their first Battle phase. This prevents first-move snowballing.

Deckout

If you must draw and your deck is empty, you lose. Be careful with aggressive draw engines — card advantage can become a liability in long games.

Hero Abilities

Each hero has a unique activated ability with a cooldown (usually 2 turns, Arkhelios is 3). Use it during your Play phase. After use, it goes on cooldown and cannot be used again until the cooldown expires.

Mystic Cancel

Heroes with M≥4 can spend 2 Energy to negate an opponent's Action card. This is a response — you declare it when the opponent plays an Action, before it resolves. Once per opponent's turn.

Conditional Effects

Many cards have "If..." clauses. "If you control a Celestial ally, deal 9 instead of 6." These check the game state at the moment the card resolves. Meeting conditions turns good cards into great ones.

9. The Six Heroes

HeroTSRMShieldEnergyTrapsAbility
Doctor Boon
The Freeborn
5324 110 5 5 Tactical Override
Once per turn: peek the top card of your opponent's deck. Cooldown: 2 turns.
High Priestess Nyra
Elemental Flame
3425 33 5 3 Luminous Convergence
First 2 times each turn you play a Mystic card, choose one: Draw 1 card OR Restore 10 Shield. Cooldown: 2 turns.
Virelia
Cradle of the Root
2333 55 4 2 Ancient Harmony
Restore 5 Shield and draw 1 card. Cooldown: 2 turns.
Sel of the Luminous
Codex of the Eternal Spark
2534 35 5 2 Arcane Archive
Reveal the top 3 cards of your deck. Choose 1 to add to your hand. Shuffle the rest back. Cooldown: 2 turns.
Ember Glow
The Ember Ashes
4334 28 5 4 Ashborn Fury
Deal 8 damage to opponent. Cooldown: 2 turns.
Arkhelios Dragon
The Void Ones
4244 35 5 4 Void Command
Opponent loses 2 Energy and discards 1 card. Cooldown: 3 turns.

Balance note: Shield values are hero-specific and calibrated through Monte Carlo simulation (15,000+ games). Every matchup falls within a 40–60% win rate. Read the full balance report →

10. Winning the Game

You win when:

⚔ Your opponent's Shield reaches zero, OR
📚 Your opponent must draw but their deck is empty (deckout)

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