Petravark

a Nightmare enters the battlefield — 151 cards in the game can cause this (Petravark is one).

1. Umbris, Fear Manifest — When Petravark enters, Umbris, Fear Manifest exiles a card from an opponent's library

a Beast creature is cast — 587 cards in the game can cause this (Petravark is one).

1. Tawnos, the Toymaker — When Petravark is cast, Tawnos, the Toymaker copies a spell

a Beast enters the battlefield — 632 cards in the game can cause this (Petravark is one).

When Petravark enters:

1. Totem Speaker — gains you 3 life
2. Wirewood Savage — draws you 1 card
3. Woodland Liege — draws you 1 card
4. Aether Charge — deals 4 damage

a land enters the battlefield — 1,560 cards in the game can cause this (Petravark is one).

When a land enters thanks to Petravark:

1. Primeval Bounty — gains you 3 life
2. Toph, Earthbending Master — puts a counter on a permanent
3. Dancing from Dark to Dawn — makes a token
4. Emeria Shepherd — brings a card back
5. Quest for the Necropolis — puts a quest counter on itself
6. Soul Stair Expedition — puts a quest counter on itself
7. Nissa of Shadowed Boughs — puts counters on a permanent
8. Thranduil, Sindarin Liege // Silvan Rally — makes a token
9. Faldorn, Dread Wolf Herald — makes a token
10. Silvan Reveler — returns itself from the graveyard

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

anything is exiled — 2,497 cards in the game can cause this (Petravark is one).

1. The War Doctor — When a land is exiled thanks to Petravark, The War Doctor puts a time counter on itself

1 other card cares about it too. These are the ones with the most connections.

anything attacks — 17,934 cards in the game can cause this (Petravark is one).

When Petravark attacks:

1. Shaun, Father of Synths — makes a token
2. Far Fortune, End Boss — deals 1 damage
3. Temmet, Naktamun's Will — draws you 1 card
4. Grim Javelineer — gives +1/+0
5. Invisible Woman — triggers
6. Caesar, Legion's Emperor — sacrifices a creature
7. Guide of Souls — triggers
8. Campsite Cuisine — sacrifices a Food
9. Gossip's Talent — triggers
10. Banon, the Returners' Leader — draws and discards

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

a creature attacks — 17,934 cards in the game can cause this (Petravark is one).

When Petravark attacks:

1. Adaptive Omnitool — searches a library
2. Anthem of Rakdos — gives +2/+0
3. Kindred Discovery — draws you 1 card
4. Invasion of New Capenna // Holy Frazzle-Cannon — puts counters on a permanent
5. Chorale of the Void — brings a card back
6. Anim Pakal, Thousandth Moon — puts a +1/+1 counter on itself
7. Saw — sacrifices a creature
8. Gisa's Favorite Shovel — makes an opponent sacrifice a creature
9. Ultima Weapon — kills a creature an opponent controls
10. Total War — kills a creature

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

a creature blocks — 17,934 cards in the game can cause this (Petravark is one).

When Petravark blocks:

1. Mage Hunters' Onslaught — makes a player lose 1 life
2. Carnage Gladiator — makes a player lose 1 life
3. Tide of War — sacrifices a creature
4. Dead-Iron Sledge — kills a creature
5. Dwindle — kills a creature

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

a nontoken creature attacks — 17,934 cards in the game can cause this (Petravark is one).

1. Mardu Ascendancy — When Petravark attacks, Mardu Ascendancy makes a token

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

a creature is cast — 18,010 cards in the game can cause this (Petravark is one).

1. God-Eternal Oketra — When Petravark is cast, God-Eternal Oketra makes a token

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

a creature enters the battlefield — 19,800 cards in the game can cause this (Petravark is one).

When Petravark enters:

1. Slash, Reptile Rampager — deals 2 damage
2. Ray Fillet, Wave Warrior — puts a counter on itself
3. The Neutrinos — gets +1/+0
4. Wingnut, Bat on the Belfry — grants flying, haste and menace
5. Aetherstorm Roc — puts a counter on a permanent you control
6. Raphael, Most Attitude — exiles a card from your library

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

anything enters the battlefield — 26,499 cards in the game can cause this (Petravark is one).

1. Prowl, Stoic Strategist // Prowl, Pursuit Vehicle — When Petravark enters, Prowl, Stoic Strategist // Prowl, Pursuit Vehicle puts a +1/+1 counter on itself
2. Path of Mettle // Metzali, Tower of Triumph — When Path of Mettle // Metzali, Tower of Triumph enters thanks to Petravark, it deals 1 damage

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