Your shoe choice for any of this events is very important. You have to consider a number of things, and most of all, you have to consider comfort. You are going to be moving a long distance for a long time and your feet are going to take a pounding.
For the Tough Mudder, I couldn’t imagine going with any other shoe than my Merrell Trail Glove.
It was the perfect shoe for the job (along with a pair of Darn Tough Socks). They had great grip for climbing and running, I never slipped. They also drained well, and protected my feet from the stumps and roots.
The only issue I had all day was more user error than anything. I was so worried about them coming off in the mud, after reading all the tales of people duct-taping their shoes on, that I decided to tie them tight and double knot them. After mile 4 or 5, they were just as tight as they were when I laced them up, and they were kinda cutting off circulation to the tops of my feet. I had to stop and untie them… which was a chore given all the packed in mud. I ended up lacing them in my normal mode and sure enough, they were perfect from there on out.
If you are looking for a shoe for Tough Mudder or any of these mud obstacle run races, pick up a pair of these. I bought mine at REI, but you can order them from Amazon at the link below.