edhseer Commander synergy, explained
Creature — Dragon Horror
Mana cost: {5}{B}{B}
Flying
At the beginning of your end step, exile the top card of each opponent's library. You may play those cards for as long as they remain exiled. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.
triggered —
triggered — taxes the table
Whenever a nonland permanent an opponent owns enters the battlefield under your control, they lose life equal to its mana value.
triggered — makes each opponent lose life equal to its mana value
Causes: exile a card, make a player lose life.
Cares about: an end step, an artifact enters the battlefield, a battle enters the battlefield, a creature enters the battlefield, an enchantment enters the battlefield, a planeswalker enters the battlefield.
hits creature — 2,298 cards in the game can cause this (Brainstealer Dragon is one).
8 other cards care about it too. These are the ones with the most connections.
put a battle onto the battlefield — 81 cards in the game can cause this.
75 other cards cause it too. These are the ones with the most connections.
put a planeswalker onto the battlefield — 366 cards in the game can cause this.
356 other cards cause it too. These are the ones with the most connections.
a Horror deals combat damage — 382 cards in the game can cause this (Brainstealer Dragon is one).
a Dragon attacks — 474 cards in the game can cause this (Brainstealer Dragon is one).
When Brainstealer Dragon attacks:
a Dragon deals combat damage — 474 cards in the game can cause this (Brainstealer Dragon is one).
When Brainstealer Dragon deals combat damage:
a nontoken Dragon enters the battlefield — 484 cards in the game can cause this (Brainstealer Dragon is one).
When Brainstealer Dragon enters:
a Dragon it applies enters with counters to — 488 cards in the game can cause this.
487 other cards cause it too. These are the ones with the most connections.
a Dragon enters the battlefield — 524 cards in the game can cause this (Brainstealer Dragon is one).
When Brainstealer Dragon enters:
4 other cards care about it too. These are the ones with the most connections.
anything is exiled — 2,497 cards in the game can cause this (Brainstealer Dragon is one).
1 other card cares about it too. These are the ones with the most connections.
life is lost — 3,160 cards in the game can cause this (Brainstealer Dragon is one).
When Brainstealer Dragon makes a player lose life:
46 other cards care about it too. These are the ones with the most connections.
put an enchantment onto the battlefield — 3,743 cards in the game can cause this.
3,733 other cards cause it too. These are the ones with the most connections.
put an artifact onto the battlefield — 4,643 cards in the game can cause this.
4,633 other cards cause it too. These are the ones with the most connections.
anything attacks — 17,934 cards in the game can cause this (Brainstealer Dragon is one).
When Brainstealer Dragon attacks:
118 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 (Brainstealer Dragon is one).
When Brainstealer Dragon attacks:
189 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 (Brainstealer Dragon is one).
90 other cards care about it too. These are the ones with the most connections.
a creature it makes cheaper to cast — 19,392 cards in the game can cause this.
19,388 other cards cause it too. These are the ones with the most connections.
a creature it boosts — 19,392 cards in the game can cause this.
19,382 other cards cause it too. These are the ones with the most connections.
a creature it grants abilities to — 19,392 cards in the game can cause this.
19,387 other cards cause it too. These are the ones with the most connections.
a creature it applies speed increase to — 19,392 cards in the game can cause this.
19,391 other cards cause it too. These are the ones with the most connections.
a creature it applies extra combat to — 19,392 cards in the game can cause this.
19,391 other cards cause it too. These are the ones with the most connections.
a creature it grants types to — 19,392 cards in the game can cause this.
19,390 other cards cause it too. These are the ones with the most connections.
a creature enters the battlefield — 19,800 cards in the game can cause this (Brainstealer Dragon is one).
When Brainstealer Dragon enters:
303 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 (Brainstealer Dragon is one).
40 other cards care about it too. These are the ones with the most connections.