How to generate a random number as damage??

Hi everyone I've just been working on a VERY basic turn based battle system (I'm still pretty new to this Construct 2 stuff) but I already have another question...

Can anyone give me an example or a method of how to generate random number as damage? Say I want it to be 4-8 vs just having an attack do 4 damage every time. I'm including my .capx file. Its NOT finished or anything just me messing with codes. on the event sheet, where it says subtract 4 from Monster.HP, what other code could I use to make it do 4-8 or something like that. 2-4, any random number? Thank you for any help or anyone that reads this!

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filedropper.com/betterbattlesystemtest my .capx

replace the 4 in the subtract with choose(4,5,6,7,8) or with floor(random(4,9))

thank you :D