Special attack button in fighting game

Hello everyone! I'm currently working on a game where you can fight against enemies. You deal damage by tapping on them and I've tried to make a function where a special attack in the form of a button is available to use once after 10 taps. When clicking on the button a random enemy should take 20 damage instead of the usual 5 damage. I'm new to programming and have no clue how to continue :sob:

Thanks in advance!

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