MULES is a playable word

mule Scrabble® Dictionary

verb
muled, muling, mules
to strike from dies belonging to two different issues, as a coin
30 Playable Words can be made from "MULES"
   2-Letter Words (7 found)
   3-Letter Words (13 found)
   4-Letter Words (9 found)
   5-Letter Words (1 found)