Destroying enemies in a layer instead of tag?

Hello, i am relatively new to unity, learning new things everyday.

i wanted to make my code as efficient as possible and though instead of using tags, i would be able to just destroy all enemies from a layer when a button is pressed(bomb button.

I have been looking and i have found a few older solutions which i have been unable to get to work, i was wondering if there was an easy way since 5.0.


Should be easy.

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