edhseer Commander synergy, explained
Land
Add {C}.
activated {T} — adds 1 mana
This land becomes a 3/3 creature with vigilance and all creature types. It's still a land.
activated {4} — turns something into a creature
activated {4} — grants a keyword
activated {4} — grants a keyword
Causes: nothing.
Cares about: nothing.
a land enters the battlefield — 1,560 cards in the game can cause this (Soulstone Sanctuary is one).
When Soulstone Sanctuary enters:
199 other cards care about it too. These are the ones with the most connections.