Grollub

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

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

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

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

life is gained — 2,076 cards in the game can cause this (Grollub is one).

When a permanent gains life thanks to Grollub:

1. Kavu Predator — puts that many +1/+1 counters on itself
2. Punishing Fire — returns itself from the graveyard

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

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

When Grollub attacks:

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

116 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 (Grollub is one).

When Grollub 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 (Grollub is one).

1. Mage Hunters' Onslaught — When Grollub blocks, Mage Hunters' Onslaught makes a player lose 1 life
2. Carnage Gladiator — When Grollub blocks, Carnage Gladiator makes a player lose 1 life
3. Barrow-Blade — When Grollub blocks, Barrow-Blade strips abilities
4. Heat of Battle — When Grollub blocks, Heat of Battle deals 1 damage
5. Battle Strain — When Grollub blocks, Battle Strain deals 1 damage
6. Favor of the Woods — When Grollub blocks, Favor of the Woods gains you 3 life
7. Tide of War — When Grollub blocks, Tide of War sacrifices a creature
8. Dead-Iron Sledge — When Grollub blocks, Dead-Iron Sledge kills a creature
9. Dwindle — When Grollub blocks, Dwindle kills a creature
10. Shield of the Righteous — When Grollub blocks, Shield of the Righteous triggers

18 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 (Grollub is one).

When Grollub attacks:

1. Mardu Ascendancy — makes a token
2. Basri Ket — makes a token
3. Militia's Pride — makes a token

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

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

301 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 (Grollub is one).

1. Prowl, Stoic Strategist // Prowl, Pursuit Vehicle — When Grollub enters, Prowl, Stoic Strategist // Prowl, Pursuit Vehicle puts a +1/+1 counter on itself

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