Yasuo vs Sion

Hit twice with Steel Tempest (Q), on minions if needed, to charge the whirlwind. Cast it during Sweeping Blade (E): the strike becomes a circle.

Keep moving before taking a trade: Way of the Wanderer (passive) builds your shield while you move, and it triggers on the first hit you take.

Chain Sweeping Blade (E) on different targets to reposition or dodge: each target has its own cooldown, so the spell comes back almost instantly.

Save Wind Wall (W) for a projectile that decides the teamfight, like Jinx's ult, rather than for poke: it blocks for 4 seconds, on a 25 to 17 second cooldown.

Watch for your allies' knock-ups: Last Breath (R) can be cast on any airborne champion, whether the knock-up comes from your whirlwind or Malphite's ult.

Leave the area while he charges Decimating Smash (Q): past 1 second of charge, the hit applies a knock-up and a stun, for up to 2.25 seconds.

Break the Soul Furnace (W) shield before he detonates it: he can only trigger it if the shield still holds.

Step to the side of Unstoppable Onslaught (R): he turns poorly once it's launched, and his charge stops on the first champion hit.

Back off as soon as he dies: during Glory in Death (passive), his autos are much faster and deal damage based on your max health, but his health drains fast.