Evilswarm Exciton Knight is a very popular card, so I am going to tell you how to beat him. The best is to get rid of him before he is even on the field using
Solemn Warning. If you don't have
Solemn Warning you can use
Bottomless Trap Hole, but the effect of
Evilswarm Exciton Knight can be chained to
Bottomless Trap Hole. If your opponent activates the effect of
Evilswarm Exciton Knight you can chain
Effect Veiler (if you don't an
Effect Veiler then you can use
Skill Drain instead) and negate his effect and attack over him on your turn. Finally you can use
Stardust Dragon or
Starlight Road to negate the activation of his effect and destroy him. If you find any other ways to beat him tell me in the comment section below.