Sure, all three of these heroes right-click to deal their damage but that's just the nature of the role. Through everything you said about Ashe/Caitlyn/Vayne... they still right-click enemies to deal damage. I don't think it's really fair to say they're the same hero because of that.
You don't play much LoL do you?
Because you can't if you just said that. Cait has 4 damaging abilities, two of them for sure a part of her damage kit in any fight. Ashe doesn't just do damage she is an AoE slow boss with a CD for slowing/controlling a fight. And Vayne's stun is a very important part of her.
They all play way differently than Dota champs, and I love my sniper to death.
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