Counting objects inside another

OK im fairly new to construct 2 still and this might sound like a silly question but here it is.

i got loads of different monsters spawned on the screen some have more of the same type then others, i what i want to do is set a bomb off which kills any monsters caught in the explosion but then i want to count how many monsters were killed in that explosion so i can deduct it off the variable of monsters alive.

please help me i cant think of anyway to do this

Whenever a monster is destroyed add 1 to a counter variable

ty didnt even noticed it had that sorry im such a noob lol

To avoid simple questions like that:

• Start with the beginner tutorial and after that do the advanced tutorial
• Before you ask a question first search on the forum and read the faq

well tbh i thought it was a rather complicated thing couldn't find anything on forums i always check them first but didn't realize it was such a simple thing i do apologise