edhseer Commander synergy, explained
Land
Add {C}.
activated {T} — adds 1 mana
Creatures you control gain deathtouch and lifelink until end of turn.
activated {2}{W}{B}, {T} — grants a keyword
Causes: nothing.
Cares about: nothing.
a land enters the battlefield — 1,560 cards in the game can cause this (Vault of the Archangel is one).
When Vault of the Archangel enters:
199 other cards care about it too. These are the ones with the most connections.