My favorite substance, both to WAM with personally, and to watch someone else get covered in, has always been THICK, GLOOPY, oatmeal. It has to be thick, and warm; and mushy/sticky for nice coverage; the runny stuff is no fun. Other than oatmeal, I like cakes and pies, warm cake batter, cake frosting etc. and if we're going the savory route then some spaghetti probably. I pretty much like everything other than shaving cream/foam, but oatmeal is DEFINITELY my favorite

Mud's my faveourite, the stickier the better. Chocolate cake mix has to be a close second. Dislikes include shaving foam and anything green.

Wallowing in mud/clay is my best but methylcellulose is a great substitute indoors

My favorite is cheese sauce. The wife is away this weekend so its a trip to sam's club for a big can of cheese. It feels great and looks so wonderful.