Riot should take some notes from Zarya (Overwatch)
Zarya's one of the toughest tanks to use in Overwatch, but also really rewarding if used right. If her shields (which she can put on both herself and on allies for brief periods of time) absorb incoming damage, they increase the firepower of her main weapon.
This kind of "block stuff, get more damage" style has only been done so far with Nocturne and Jax (IIRC), but they aren't damage-absorbing shields. A Champion with a Zarya-like mechanic would be a lot of fun, IMO, if a tad frustrating to the enemy. But there'd be clear counterplay: "Don't attack the shields, they don't last long!"
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