Blind Effect

Status: Designed Author: Nathan + game-designer Last Updated: 2026-04-07 System Index: Extension of Status Effect System (#7) and Enemy Data & AI (#6)

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1. Overview

Blind is a status effect applied to the player that hides enemy intents for the duration of the effect. While blinded, the intent display for all living enemies is replaced with a concealment overlay — the player cannot see what any enemy will do on their next turn. Blind is a pure information denial mechanic: it does not change the dice, reduce damage, or alter scoring. The only thing it takes away is the player's ability to plan around incoming enemy actions. Blind lasts for exactly 1 turn by default, though specific sources can apply extended durations. The effect expires at the end of the player's scoring phase (before the enemy phase executes), meaning the player plays their hand without the information, and the reveal happens as enemies act — not before.

The system is introduced through the Merchant's POCKET_SAND action (shop combat) and can appear on select interference-type enemies in later floors. It integrates with the existing Status Effect System as a new TIMED debuff with a new modifier_type of INFORMATION_DENY, and hooks into the Dice Combat UI's intent rendering pipeline.

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2. Player Fantasy

The terror of playing blind. Most of the game is about reading the battlefield — "the skeleton is attacking for 12, the shaman is about to heal, I should kill the shaman." Blind strips that away. For one turn, the player is flying without instruments.

The fantasy has two moments:

1. The panic moment — the intent icons go dark. The player has to make a decision with incomplete information. Do they prioritize the enemy most likely to deal damage? Kill the most dangerous target even without confirmation? Use a consumable as insurance? This engages the player's pattern recognition ("I know what this enemy type usually does") and tests their mental model of enemy behaviors.

2. The resolution moment — the player scores and commits. Then the enemy phase plays out. Finding out what was hidden is a small dramatic beat — relief if enemies did nothing devastating, dread if the hidden action was exactly what the player feared.

Secondary fantasy: counterplay mastery. Veteran players will know which relics counter blind and keep them specifically for floors where blinding enemies appear. Recognizing the Merchant's POCKET_SAND setup and having a Clarity Lens relic ready feels like reading an opponent.

Target MDA aesthetics: Challenge (primary — plays without information), Discovery (secondary — learning enemy behavior by heart to compensate), Fantasy (tertiary — the world pushes back in unexpected ways).

This mechanic does NOT serve Submission (relaxation). Blind is a tension spike, not a comfort mechanic. It should be used sparingly.

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3. Detailed Design

3.1 Core Rules

1. Blind is a status effect ("blind") applied to the player, not enemies.
2. While blind is active (stacks > 0), all enemy intent displays are hidden.
3. Blind hides intent only — enemy HP bars, shield values, and status effect icons on enemies remain fully visible. The player can still see how healthy enemies are and what statuses they carry; they just cannot see the action those enemies will take next.
4. Blind uses DurationType.TIMED. Duration is measured in player turns: the stack count decreases by 1 at the start of the player's phase (before the player rolls dice).
5. Blind stacks extend duration, they do not intensify effect. Applying Blind 2 to a player already at Blind 1 results in Blind 3 (3 turns hidden).
6. When Blind expires (stacks reach 0), intent icons are immediately restored. The restore happens before the player rolls, so the player always enters their turn with full information unless they are currently blinded.
7. Blind is a debuff (is_debuff = true). Future cleanse mechanics (consumables, relics, shrine blessings) can remove it.
8. Multiple sources of Blind (e.g., Merchant + a Shadow Rogue in the same encounter) stack additively on duration. The player can accumulate multiple blind turns.

3.2 What Is Hidden vs. Visible During Blind

The hover tooltip is also suppressed while blind is active. The player cannot work around the visual by hovering — the information is simply unavailable.

3.3 Visual Treatment

Intent display during Blind:

• The intent icon slot is replaced with a solid "?" icon (or a closed eye icon, per art direction). Use the existing 1-bit art style.
• A subtle desaturated overlay (greyscale tint, ~30% opacity) appears over each enemy's intent area — not the whole enemy sprite, just the intent badge.
• The targeting label beneath each enemy reads: "???" instead of the normal action description.
• A status indicator on the player HUD shows the Blind debuff icon with the remaining stack count (same visual system as existing status icons).

Blind application animation:

• When Blind is applied, the intent icons "close" with a brief fade-to-grey animation (~0.3 seconds). This is not a screen-wide effect — only the intent badges animate.
• Optional: brief screen-edge darkening pulse (vignette flash, 1 frame) to communicate "something happened to you."

Blind expiry animation:

• At the start of the player's turn when stacks hit 0, intent icons "open" with a fast fade-in (~0.2 seconds).
• No fanfare. The reveal is understated — the icons just come back.

3.4 Enemy Usage — Who Can Blind?

Blind is a rare, high-value interference. It should feel notable when it appears, not routine. Placement follows the principle: blind appears on enemies whose thematic identity centers on deception, misdirection, or information warfare.

Tier 1 — Existing enemy: Merchant (POCKET_SAND)

Already defined in shop-combat-system.md. The Merchant applies Blind 1 with 20% action weight. This is the player's introduction to blind in a controlled context (a chosen fight with a known, special enemy).

Tier 2 — New interference-type enemies (recommended additions)

The following enemies are designed to carry Blind as their primary interference. These are proposals — the enemy database owner should review for balance fit:

Design constraint: no more than 1 blinding enemy per encounter. The blind effect is disruptive enough that stacking it across multiple enemies in one fight would feel oppressive rather than interesting. If the encounter generator places multiple blinding enemies together, one of them should have its Blind action weighted out (set weight to 0 for that encounter slot).

Tier 3 — Arch Demon passive consideration

The Arch Demon's Phase 2 (boss-specific) can include a DREAD_AURA action that blinds for 1 turn. This is a thematic fit (Act 3 boss creating dread and uncertainty) and a late-game skill test. It should appear at most once per phase.

3.5 Counterplay

Blind is meaningful only if the player has counterplay options. The following counterplay vectors are designed into the system:

Intrinsic counterplay (no items required):

• Enemy behaviors are learnable. Veteran players who have memorized what Shadow Rogues and Smoke Cultists do can play optimally even without seeing the intent. Pattern AI enemies follow fixed sequences — a player who counts turns knows exactly what's coming.
• The player can still see enemy HP and statuses, so priority targeting (kill the low-HP enemy, focus the burning one) remains available.
• If an enemy is the only surviving enemy, the player knows the intent must be one of that enemy's possible actions. Narrowing the possibility space is a skill expression.

Relic counterplay:

Consumable counterplay:

Elemental counterplay:

• Freeze applied to a blinding enemy prevents that enemy from executing their next action. Freezing an enemy before they can apply Blind wastes their turn. This is the primary offensive counterplay — control the enemy, deny the blind.
• Wind combo (Frost Lance, Tempest) AoE can freeze multiple enemies simultaneously, shutting down coordinated blind setups.

Cleanse mechanic (future-proofing):

The Status Effect System already notes a future cleanse mechanic. When cleanse is implemented, Blind (is_debuff = true) should be cleansable. Any cleanse consumable, relic, or shrine blessing should remove Blind along with other debuffs.

3.6 Interaction with Interference System

Blind is a status effect, not an interference type. Interference types (SNIPE, CHAOS, etc.) are instantaneous effects that happen during the enemy phase. Blind is a persistent debuff that affects the player's information state across a full player turn.

The two systems coexist:

• POCKET_SAND (Merchant action) applies the Blind status during the enemy phase, taking effect immediately — the player's next turn will be blinded.
• If a CHAOS interference also fired the same enemy phase, the dice are scrambled AND the player plays next turn without knowing what enemies will do. Stacked pressure is intentional for the Merchant encounter.
• Blind does not prevent or modify any interference type. If a die is SNIPED while the player is blind, the snipe still happens normally. The player still sees the die being affected.

3.7 Interaction with Per-Enemy Turn Limit

The turn limit is unchanged by Blind. The player has the same number of turns to defeat the enemy whether blinded or not. Blind does not pause or reset the turn counter.

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4. Formulas

4.1 Blind Duration

applied_blind_stacks = source_base_stacks

if target already has "blind":
    target.statuses["blind"].stacks += applied_blind_stacks
else:
    target.statuses["blind"] = { stacks: applied_blind_stacks }

Where source_base_stacks is defined per enemy action:

4.2 Blind Tick (Duration Decrease)

Blind is DurationType.TIMED. Ticking follows the existing tick rule:

# At the START of the player's turn:
if player has "blind":
    player.statuses["blind"].stacks -= 1
    if player.statuses["blind"].stacks <= 0:
        remove_status(player, "blind")
        signal blind_expired  # Triggers intent reveal animation in UI

This means:

• Blind applied during the enemy phase of Turn N → player is blinded during Turn N+1, expires at the start of Turn N+2.
• Blind 2 applied → player is blinded during Turns N+1 and N+2, expires at Turn N+3.

4.3 Smelling Salts Relic Interaction

# Called during apply_status, before committing:
if player has relic "smelling_salts":
    applied_blind_stacks = max(0, applied_blind_stacks - 1)
    if applied_blind_stacks == 0:
        return  # Blind fully absorbed, nothing applied

Net result: Smelling Salts converts Blind 1 into no effect, Blind 2 into Blind 1, Blind 3 into Blind 2.

4.4 Oracle's Monocle Relic Interaction

# In damage calculation, after base scoring:
if player has "blind" and player has relic "oracles_monocle":
    final_damage *= 1.10

Applies to hand damage only, not elemental combo bonus damage.

4.5 Eye Drops Consumable

# On use:
if player has "blind":
    remove_status(player, "blind")
    signal blind_expired  # Same intent reveal animation as natural expiry
else:
    # No-op — consumable still consumed (wasted use, player's mistake)

Consumable is wasted if used while not blinded. This is consistent with how other consumables behave on null targets.

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5. Edge Cases

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6. Dependencies

Upstream (systems this depends on)

Implementation note — StatusModifierType: The existing StatusModifierType enum covers damage and block math. INFORMATION_DENY is a new type that does not modify combat math — it modifies UI rendering. The cleanest implementation is to add INFORMATION_DENY to the enum and handle it as a special case in the UI layer (the Combat UI queries whether the player has "blind" and hides intents accordingly), rather than having the Status Effect System's query functions handle it.

Implementation note — EnemyTarget: Existing targets are ALL_PLAYERS, RANDOM_PLAYER, SELF, ALL_ENEMIES. The blind action targets the player. In solo, this is equivalent to ALL_PLAYERS or RANDOM_PLAYER (same result). For implementation, use ALL_PLAYERS for DEBUFF actions targeting the player to keep the schema consistent with any future multiplayer consideration.

Downstream (systems that must be aware of this)

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7. Tuning Knobs

All values live in assets/data/status_effects/blind.tres and assets/data/relics/ (per relic). None hardcoded.

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8. Acceptance Criteria

All criteria must pass before this feature ships. Each criterion maps to a specific, verifiable behavior.