Trial // Error

an instant is cast — 3,931 cards in the game can cause this (Trial is one).

When Trial // Error is cast:

1. Electro, Assaulting Battery — adds 1 mana
2. Lunar Mystic — draws you 1 card
3. Ojer Pakpatiq, Deepest Epoch // Temple of Cyclical Time — grants rebound
4. Repeated Reverberation — copies an ability
5. Riku of Two Reflections — copies a spell
6. Sword of Wealth and Power — copies a spell
7. Gale, Waterdeep Prodigy — brings a card back
8. In the Eye of Chaos — counters a spell
9. Lilah, Undefeated Slickshot — exiles a spell you control
10. Niblis of Frost — taps a creature an opponent controls

427 other cards care about it too. These are the ones with the most connections.

a nontoken creature leaves the battlefield — 4,133 cards in the game can cause this (Trial is one).

1. Dual Nature — When a creature leaves the battlefield thanks to Trial // Error, Dual Nature exiles a creature

3 other cards care about it too. These are the ones with the most connections.

a creature leaves the battlefield — 4,238 cards in the game can cause this (Trial is one).

When a creature leaves the battlefield thanks to Trial // Error:

1. Extractor Demon — mills a card
2. Valor of the Worthy — makes a token
3. Traveling Plague — returns itself from the graveyard
4. Funeral March — makes a player sacrifice a creature

25 other cards care about it too. These are the ones with the most connections.

anything is cast — 31,128 cards in the game can cause this (Trial is one).

When Trial // Error is cast:

1. Windrider Wizard — draws you 1 card
2. Relic Amulet — puts a charge counter on itself
3. Rockslide Sorcerer — deals 1 damage
4. Umara Wizard // Umara Skyfalls — grants flying
5. Alania, Divergent Storm — makes an opponent draw 1 card
6. Umara Mystic — gets +2/+0
7. Master of Winds — triggers

5 other cards care about it too. These are the ones with the most connections.