Here's a 'better' idea...

In the mist your attacks have a 30% chance to miss and do no damage and enemies have a 10% chance to critical from a sneak attack. Also the mist follows you around so once you leave the biome it stays with you like the wet condition unless a wisp removes it for you.

When wet inside the mist you take frost damage even with a frost resistance and if you stay in the mist too long you randomly teleport to another cloud of mist.