edhseer Commander synergy, explained
Instant
Mana cost: {1}{U}
Counter target spell unless its controller pays {2}.
on-cast —
Counter that spell instead if its controller has three or more poison counters.
on-cast —
Causes: counter a spell.
Cares about: nothing.
an instant is cast — 3,931 cards in the game can cause this (Bring the Ending is one).
When Bring the Ending 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 (Bring the Ending is one).
When Bring the Ending is cast:
5 other cards care about it too. These are the ones with the most connections.