It's a little out of character as Vigor prevents critters from dying due to damage and the Fog Crawler definitely could die when fed enough bullets, but it's at least got the same butt-clenching vibe as the Fallout Fog Crawler
The Gitrog Monster is a fun Lands commander because you just get to churn through your deck at such a rapid pace
They give you three colors, so that gives you options
I find I end up only playing it in decks that want a high artifact count and have good synergy with them as middle curve filler, quite a lot like Solemn Simulacrum
Day of Judgment and Shatter the Sky are some such alternatives, and still perform admirably in most scenarios
Gaining life when your opponents creatures die is a needed benefit when youre playing against aggro or go-wide, and if youre sacrificing your creatures for value, thatll hurt other players