Doomsday

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

1. The War Doctor — When Doomsday is exiled, The War Doctor puts a time counter on itself

life is lost — 3,160 cards in the game can cause this (Doomsday is one).

When Doomsday makes a player lose life:

1. The Master of Lake-town — mills a card
2. Intermediate Chirography — puts a counter on a creature
3. Vilis, Broker of Blood — draws you that many cards
4. Vengeful Warchief — puts a +1/+1 counter on itself
5. Wax-Wane Witness — gets +1/+0
6. Oath of Lim-Dûl — sacrifices an enchantment
7. Marina Vendrell's Grimoire — triggers
8. Lich's Mastery — triggers
9. Lich's Tomb — sacrifices a permanent
10. Gonti's Machinations — puts a counter on a permanent you control

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

a sorcery is cast — 3,720 cards in the game can cause this (Doomsday is one).

When Doomsday is cast:

1. Spellweaver Volute — copies a spell
2. Lilah, Undefeated Slickshot — gets +1/+1
3. Niblis of Frost — gets +1/+1
4. Primeval Bounty — puts 3 counters on a creature
5. Tetsuko Umezawa, Pursuer — gets +1/+1
6. Thor, God of Thunder — deals that spell's mana value damage
7. Krile Baldesion — brings a card back
8. Summon: Good King Mog XII — makes a token
9. Kykar, Wind's Fury — makes a token
10. Blood Funnel — sacrifices a creature

424 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 (Doomsday is one).

When Doomsday 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.