Moor Fiend

Creature — Horror3/3$0.23

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Legal in Commander

Is

Commanders whose abilities work with this card and share its colors, from what the cards do.

Captain N'ghathrodMoor Fiend is a Horror, which Captain N'ghathrod can use.
Umbris, Fear ManifestMoor Fiend is a Horror, which Umbris, Fear Manifest can use.