Drowned

a Zombie deals combat damage — 657 cards in the game can cause this (Drowned is one).

1. Undead Alchemist — When Drowned deals combat damage, Undead Alchemist mills a card

a Zombie attacks — 657 cards in the game can cause this (Drowned is one).

1. Varina, Lich Queen — When Drowned attacks, Varina, Lich Queen draws you that many cards

a nontoken Zombie enters the battlefield — 661 cards in the game can cause this (Drowned is one).

1. Necroduality — When Drowned enters, Necroduality makes a token

a Zombie enters the battlefield — 795 cards in the game can cause this (Drowned is one).

1. Noxious Ghoul — When Drowned enters, Noxious Ghoul shrinks a creature by -1/-1
2. Geralf, the Fleshwright — When Drowned enters, Geralf, the Fleshwright puts counters on a permanent
3. Wayward Servant — When Drowned enters, Wayward Servant makes each opponent lose 1 life
4. Champion of the Perished — When Drowned enters, Champion of the Perished puts a +1/+1 counter on itself
5. Mummy Paramount — When Drowned enters, Mummy Paramount gets +1/+1
6. Unconventional Tactics — When Drowned enters, Unconventional Tactics returns itself from the graveyard
7. Binding Mummy — When Drowned enters, Binding Mummy taps a creature or artifact

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

When Drowned 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

111 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 (Drowned is one).

When Drowned 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 (Drowned is one).

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

When Drowned attacks:

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

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

When Drowned deals combat damage:

1. Locutus of Borg — makes a token
2. Antagonist Incorporator — makes a token
3. Hive Mind Coprocessor — makes you lose life

194 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 (Drowned is one).

When Drowned is cast:

1. Primeval Bounty — makes a token
2. Bloodbond March — brings a card back
3. Dancing from Dark to Dawn — puts that spell's mana value counters on a creature
4. Endrek Sahr, Master Breeder — makes that spell's mana value tokens
5. Summon: Fenrir — it arrives with counters thanks to Summon: Fenrir
6. Summon: Brynhildr — grants haste

85 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 (Drowned is one).

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

300 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 (Drowned is one).

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

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