Why does Lee sin ult have a mini stun but Darius ult doesn't?

Because Lee Sin is displacing them, and his is often used as an opener to a fight.

Darius is just jumping at them and murdering them, and his is only ever used as an execute.

You might as well ask why Garen's R doesn't have a mini-stun.

Basically, Riot didn't like people being able to use flash to reposition themselves before the knockback. They'd generally use this to have his ultimate knock them back towards safety.

However, they seem perfectly fine with Lee Sin using flash to redirect the knockback.

Why does Darius ult do true damage but Lee Sin ult doesn't?

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