Omniscience

a spell is cast — 155 cards in the game can cause this (Omniscience is one).

When a spell is cast thanks to Omniscience:

1. Glaring Fleshraker — makes a token
2. The Kingpin of Crime — drains each opponent
3. Leader's Talent — puts a counter on a creature
4. Nita, Forum Conciliator — puts a counter on a creature
5. Treasury Thrull — drains each opponent
6. Life Insurance — drains each opponent
7. Sorin of House Markov // Sorin, Ravenous Neonate — drains each opponent
8. Syndicate Heavy — drains each opponent
9. Norin the Wary — flickers itself
10. Desecration Elemental — makes a player sacrifice a creature

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

an enchantment is cast — 3,673 cards in the game can cause this (Omniscience is one).

When a spell is cast thanks to Omniscience:

1. Hallowed Haunting — makes a token
2. Daxos the Returned — puts a counter on a permanent
3. Tatsunari, Toad Rider — makes a token
4. Sythis, Harvest's Hand — gains you 1 life
5. Sigil of the Empty Throne — makes a token
6. Dawnhart Geist — gains you 2 life
7. Herald of the Pantheon — gains you 1 life
8. Kami of Transience — puts a +1/+1 counter on itself
9. Argothian Enchantress — draws you 1 card
10. Mesa Enchantress — draws you 1 card

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

a nontoken enchantment enters the battlefield — 3,691 cards in the game can cause this (Omniscience is one).

1. Historian's Boon — When Omniscience enters, Historian's Boon makes a token

an enchantment enters the battlefield — 3,743 cards in the game can cause this (Omniscience is one).

When Omniscience enters:

1. Calix, Guided by Fate — puts a counter on a creature
2. Elvish Archivist — draws you 1 card
3. Victor, Valgavoth's Seneschal — surveils
4. Strength from the Fallen — gives +X/+X, where X is the number of creature cards in your graveyard
5. Doomwake Giant — shrinks a creature by -1/-1
6. Cacophony Unleashed — turns something into a creature
7. Ghostly Dancers — makes a token
8. Thassa's Devourer — mills a card
9. Killian, Decisive Mentor — taps a creature
10. Thoughtrender Lamia — makes an opponent discard a card

64 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 (Omniscience is one).

1. Nature's Wrath — When Omniscience enters, Nature's Wrath makes a player sacrifice an Island or permanent

28 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 (Omniscience is one).

When a spell is cast thanks to Omniscience:

1. Sokka, Bold Boomeranger — puts a +1/+1 counter on itself
2. Captain Jean-Luc Picard — makes a token
3. Windrider Wizard — draws you 1 card
4. Relic Amulet — puts a charge counter on itself
5. Rockslide Sorcerer — deals 1 damage
6. Umara Wizard // Umara Skyfalls — grants flying
7. Alania, Divergent Storm — makes an opponent draw 1 card
8. Umara Mystic — gets +2/+0
9. Saheeli, Radiant Creator — puts a counter on a permanent you control
10. Master of Winds — triggers

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