Teenage, over concerned sand bender
Milt often get's paranoid about things, wanting to stay where he knows it is safe, and not in the unknown. He is very caring about the others around him, but does not like to be touched by anyone. Ever.
Any earth, but better with sand and pebbles then large rocks. However, Milt can mold his sand into large shapes and use them as weapons. Also, randomly, he carries a small pocket knife in his sleeve pocket, as well as a tarnished silver, old fashioned key in his right pant's pocket.