Screeching Bat // Stalking Vampire

In Commander, Screeching Bat // Stalking Vampire is a low-priority include outside of dedicated day/night or vampire tribal builds — the upkeep cost to maintain Stalking Vampire form competes with everything else you want to be doing, and a 5/5 trampler is underwhelming at the mid-to-late stages of a four-player game. Legacy and Vintage are non-starters; three-mana creatures that require ongoing mana investment don't survive contact with those formats. Modern is where the card has the most theoretical relevance, but vampire aggro there prefers one- and two-drops, so it rarely makes the cut. The clearest home is a Commander deck that specifically cares about day/night transitions — Tovolar, Dire Overlord // Tovolar, the Midnight Scourge and Wilhelt, the Rotcleaver adjacent builds — where the transformation trigger becomes a feature rather than a tax.