Arcane Sanctum

Arcane Sanctum shows up in thousands of Commander and constructed lists as a staple in its role. EDHREC and tournament data confirm it is widely played — not because it is broken, but because it efficiently fills a slot in your curve or interaction package.

In deckbuilding: Land — mana or utility. Tune the number of copies to your format (1 in Commander, up to 4 in 60-card). If your deck lacks an answer to what this card does, consider sideboard slots or a same-mana-cost alternative.