I wouldn't run slicks if I knew there was wet clay under mud puddles, that stuff can take you down fast with how slippery it can be. If I knew it was going to be a lot of wet and mud I'd want a basic set of fenders, the kind the zip ties to the stays and fork legs and keeps the worst of it from running down your back or into your water bottle. The Pirelli look like they're designed for this. The Vittoria Mezcal seems to have a lot of good reviews for the great divide race for its ability to handle the mud but still roll quick on pavement. Might be worth a look.