edhseer Commander synergy, explained
Instant
Mana cost: {W}
Cast this spell only during an opponent's upkeep.
Creatures can't attack this turn.
on-cast — restricts attacking or blocking
Causes: nothing.
Cares about: nothing.
an instant is cast — 3,931 cards in the game can cause this (Festival is one).
When Festival is cast:
427 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 (Festival is one).
When Festival is cast:
5 other cards care about it too. These are the ones with the most connections.