The Wishlist for Regular Summonings is a way to establish which heroes for each class you prefer.

After selecting 1 hero for each class on your wishlist, Players will enjoy a higher probability of drawing those heroes via Regular Summonings. (The overall probability of summoning SSR heroes will not change.)
When Regular Summonings draw Elite heroes in 5 consecutive summonings, the next Elite hero drawn will be the hero from your Wishlist. This does not apply to Temple or Abyss heroes.