edhseer Commander synergy, explained
Instant
Mana cost: {1}{U}{U}
This spell costs {U} less to cast if an opponent cast two or more spells this turn.
on-cast — costs {U} less
Counter target spell.
on-cast —
Causes: counter a spell.
Cares about: nothing.
an instant is cast — 3,931 cards in the game can cause this (Ertai's Scorn is one).
When Ertai's Scorn 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 (Ertai's Scorn is one).
When Ertai's Scorn is cast:
5 other cards care about it too. These are the ones with the most connections.