Yasuo vs Veigar

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.

If Event Horizon (E) lands around you, stay inside: only the edge stuns, and the cage disappears after 3 seconds.

Get out of the Dark Matter (W) zone as soon as the spell shows: it hurts a lot, but falls from the sky with a delay.

Dodge his spells and deny him kills: with Phenomenal Evil Power (passive), each spell that hits a champion and each takedown gives him power.

Once he hits level 6, don't stay in his range at low health: Primordial Burst (R) deals more damage based on your missing health, peaking below 33%.