He is "okay". He can do his job, but he is purely early game. If he doesn't get kills and start snowballing himself/lanes, he is pretty useless. In fights, he doesn't offer much as he only Q's to his target and tries to kill them. Early on is when he can do this easily, as people don't have much hp, but as they level up and get items, he starts losing the ability to do this unless he himself starts getting kills(gold inflow). His CC as also very situational, as it is strong, but its been used so much people don't really endlessly facecheck bushes for him to walk into. Also with how easy warding is now, he can be warded out pretty easily. He is counter hard by greens, something you usually wouldn't expect from an "invisi" champion.
Your late game is where you will run into problems. Unless you got fed or catch out a support or something, you probably won't be able to 1v1 people. You don't offer much in teamfight outside of damage and usually people will sit back to wait for you to go in to kill you. At this point you're best served split pushing, though the problem is in the current meta, split pushers have TP. As you won't have TP, you won't be able to make much of an impact unless you can 1v1 the person who has TP and kill them/force them off.
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