Minismallholding got it :). So the !special attack is allowed once you reach level3, you can use it instead of a basic or difficult attack if you want. You will know if it failed if your hands melt or your head explodes...you know if it wins if you get a score...from memory it will be 15 hit points!!!
During the boss round if you use the special attack for your attacks if you want. @doughtaker will add your ibtluckydip item and your gobbodrop item manually to your score if your special succeeds.
It is 15 indeed, as @doctorcrypto demonstrated during Stage 5.