edhseer Commander synergy, explained
Creature — Leviathan
Mana cost: {6}{U}{U}
When this creature enters, return all other nonland permanents to their owners' hands.
triggered — bounce
Unearth {6}{U}
Causes: an artifact leaves the battlefield, a battle leaves the battlefield, a creature leaves the battlefield, an enchantment leaves the battlefield, a planeswalker leaves the battlefield.
Cares about: nothing.
an enchantment leaves the battlefield — 1 card in the game can cause this (Kederekt Leviathan is one).
anything leaves the battlefield — 1 card in the game can cause this (Kederekt Leviathan is one).
hits creature — 2,298 cards in the game can cause this.
12 other cards care about it too. These are the ones with the most connections.
an artifact leaves the battlefield — 1,680 cards in the game can cause this (Kederekt Leviathan is one).
a nontoken creature leaves the battlefield — 4,133 cards in the game can cause this (Kederekt Leviathan is one).
When a creature leaves the battlefield thanks to Kederekt Leviathan:
1 other card cares about it too. These are the ones with the most connections.
a creature leaves the battlefield — 4,238 cards in the game can cause this (Kederekt Leviathan is one).
21 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 (Kederekt Leviathan is one).
When Kederekt Leviathan attacks:
112 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 (Kederekt Leviathan is one).
When Kederekt Leviathan attacks:
181 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 (Kederekt Leviathan is one).
When Kederekt Leviathan blocks:
23 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 (Kederekt Leviathan is one).
When Kederekt Leviathan attacks:
1 other card cares 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 (Kederekt Leviathan is one).
When Kederekt Leviathan enters:
299 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 (Kederekt Leviathan is one).
42 other cards care about it too. These are the ones with the most connections.