EMP- It is in my opinion one of the best retake and entry util in the game. First of all it is free info and second it suppresses your abilities which means that you cannot stop pushes with util like mollies and sucks. Most teams tend to play Astra and Kay/0 is the best counter if he manages to suppress her. Also, it suppresses ultimates which means you can't be too close to Kay/0 if you are already using your ultimate.
Flashbang- His flashbang is self sufficient and can also be used for team pushes. I think it is the second best flash in the game after Skye's bird and can be dangerous if used properly.
Charge Grenade- His molly is really powerful which means you can stop pushes or hurt enemies who are pushing you for easy gunfights. It is a really good time stall and also useful in post plants with lineups.
Null/CMD- His ultimate is definitely not better than his other util but it is really good for entry and holding pushes. You also have the option to be resurrected if you are downed and also suppress enemies. The increased fire rate is also useful for good phantom users.
IMO Kay/0 is going to stay in the meta until his knife gets nerfed to only suppress enemies within it's line of sight.
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