Strangle

In Commander, Strangle earns its slot in Imodane, the Pyrohammer decks specifically; everywhere else, one-mana removal that misses large creatures is too conditional against 40-life tables full of haymakers. In Pauper it's a legitimate consideration — the format runs low to the ground and one mana at instant speed trades efficiently with most threats. Modern and Pioneer have enough efficient competition that Strangle rarely makes the cut outside of budget builds or very specific aggro sideboards. Legacy and Vintage don't want it; the creatures worth killing there ignore the power restriction entirely.