Fertilid

an Elemental enters the battlefield — 754 cards in the game can cause this (Fertilid is one).

When Fertilid enters:

1. Champion of the Path — deals its power damage
2. Risen Reef — puts a land onto the battlefield

a library is searched — 982 cards in the game can cause this (Fertilid is one).

When a land searches a library thanks to Fertilid:

1. River Song — puts a +1/+1 counter on itself
2. Archivist of Oghma — gains you 1 life
3. Wan Shi Tong, Librarian — puts a +1/+1 counter on itself
4. Ob Nixilis, Unshackled — makes an opponent sacrifice a creature

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

When a land enters thanks to Fertilid:

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. Silvan Reveler — returns itself from the graveyard
10. Floral Evoker — puts a +1/+1 counter on itself

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

a creature gets a counter — 2,691 cards in the game can cause this (Fertilid is one).

When Fertilid gets a counter:

1. Hollowmurk Siege — draws you 1 card
2. Ant-Man, Colony Commander — makes a token
3. Earth Kingdom General — gains you that much life
4. Casey Jones, Back Alley Brute — deals that much damage
5. Generous Patron — draws you 1 card
6. Shalai and Hallar — deals that much damage
7. Danny Pink — draws you 1 card
8. Enduring Scalelord — puts a +1/+1 counter on itself
9. Bold Plagiarist — puts counters on a permanent
10. Mikey & Leo, Chaos & Order — draws you 1 card

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

anything gets a counter — 4,415 cards in the game can cause this (Fertilid is one).

1. All Will Be One — When Fertilid gets a counter, All Will Be One deals that much damage

8 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 (Fertilid is one).

When Fertilid 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. Three Dog, Galaxy News DJ — sacrifices an Aura

113 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 (Fertilid is one).

When Fertilid 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

182 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 (Fertilid is one).

When Fertilid 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 creature deals combat damage — 17,934 cards in the game can cause this (Fertilid is one).

1. Primo, the Unbounded — When Fertilid deals combat damage, Primo, the Unbounded makes a token

196 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 (Fertilid is one).

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

2 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 (Fertilid is one).

When Fertilid enters:

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

309 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 (Fertilid is one).

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

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