edhseer Commander synergy, explained
Land
This land enters tapped unless you control an Island.
Add {U}.
activated {T} — adds 1 mana
The next spell you cast this turn has improvise.
activated {U}, {T} — grants a keyword
Causes: nothing.
Cares about: nothing.
a land enters the battlefield — 1,560 cards in the game can cause this (Archway of Innovation is one).
When Archway of Innovation enters:
199 other cards care about it too. These are the ones with the most connections.