Someone Explain Irelia

I never thought of her as OP either, but I do like her dueling playstyle which I've seen ICU demonstrate several times.

Hm let's see, she has a passive that gives her free tenacity. When most champs get snowballed you shut them down with CC, but you know I'm Irelia can't do that. Does true damage so armor isn't the most beneficial (it is, but doesn't completely shut down her damage like other AD champs). Oh you won a trade with her? Nah dude she's got million second stun based on your health being higher than hers.

TL;DR When she snowballs, she is incredibly hard to shut down because what counters other champions snowballing is CC does not affect Irelia much.

She can kill squishy champions and there isn't much you can do as a team to stop her. Her passive makes it so she can't be locked down for very long, she has very good sustain, true damage based on autos, a gapcloser, and a situational stun. So she runs through your entire team, taking a bit of damage so that when she jumps on you, the squishy damage dealer, she can now stun you for long enough that when you're unstunned you're dead. You can't simply kill her because she's got that built in sustain and any intelligent Irelia player builds full tank after triforce. The only thing you can do is use knockups and knockbacks since they aren't affected by tenacity.

Cant CC her.

Good dash. Can farm easy with it.

On hit healing and true damage

Magic damage burst that can be up to 2 seconds of a stun which is easy for her to win fights with. Just keep chunking them for true damage.

Ult gives even more farming and healing, low cooldown.