Shroom and Gloom Wikibuild 3271281

How rewards work

Where a card can come from, and what decides how good it is. The rules below are read out of the game's own code, so the numbers are the ones the game rolls against.

Two decks, built separately

You build two decks in one run and they never mix. The combat deck is what you play in a fight; the explore deck is what you spend moving through the dungeon, opening things and upgrading cards. The build carries 501 combat cards and 475 explore cards, and every card belongs to one deck or the other — a card page says which.

Rewards come out of pools

The game never picks a card from the whole set. Each place that offers you a card — a fight, a chest, a shop, a dig — draws from a named pool, and a pool is just a list of cards. There are 124 pools holding cards that ship with the game. A card page lists every pool it sits in, which is the direct answer to where you can find it.

Depth decides rarity, not luck alone

Pools that care about rarity come in three lists — common, uncommon and rare. Which list a reward is drawn from is rolled from how deep you are, and the roll is narrow enough that the outcome is often fixed. The game adds a per-depth modifier to a roll of four values, then reads the result: under 5 is common, under 10 is uncommon, 10 or more is rare.

That makes the distribution exact rather than approximate:

DepthCommonUncommonRare
0100%0%0%
1100%0%0%
2100%0%0%
3100%0%0%
475%25%0%
550%50%0%
625%75%0%
70%100%0%
80%100%0%
90%100%0%
100%75%25%
110%50%50%
120%25%75%
130%0%100%
140%0%100%
150%0%100%

So rare cards cannot appear before depth 10, and from depth 13 every tiered reward is rare. The first uncommon appears at depth 4. Going deeper is the only way to raise the tier.

When a pool cannot supply the tier

If the rare list has nothing valid left to offer — everything in it is already in the offer, blocked, or at its limit — the game steps down rather than failing: rare falls back to uncommon, uncommon to common, and common to a designated last-resort card. A deep run that keeps showing commons has usually exhausted the higher lists, not rolled badly.

What stops a card being offered

What a card costs to play

The number on a card is not always what you pay. The cost the game charges is the card's energy cost, plus any temporary cost stuck to it, plus its gunk when gunked cards can be played at all. Gunk is therefore a tax on the card it lands on, not a separate resource you spend.