Syndra vs Locke

Place Dark Sphere (Q) between you and your target, then cast Scatter the Weak (E): the sphere you push stuns the enemies it hits.

After landing Force of Will (W), follow up right away with Dark Sphere (Q): the target is slowed and has a hard time dodging it.

Poke with Dark Sphere (Q) from level 1: it has 800 range, its cooldown is only 7 seconds, and each rank of your ult lowers it further.

Hit enemies whenever you can: Transcendent (passive) gives you Splinters of Wrath for every level and every hit, and each threshold upgrades one of your spells.

Place several spheres before Unleashed Power (R): the ult launches the 3 orbiting you at your target, plus up to 4 more nearby.

Back instead of staying in lane at low health: Silver Stake (passive) adds damage to his autos that grows with your missing health.

Trade after Ashen Pursuit (E): it's his only instant movement, and its 10-second cooldown only resets if he gets a takedown.

During Soul Ignition (W), only hit him if you can kill him: at the end, he heals back part of the last damage taken, yours included.

Marked by Purgatory (R), stay above its threshold: if you have a heal or a shield, use it, because he seals marked enemies who drop below it.

If the Purgatory (R) artifact lands, hold the area where it fell: by picking it up, Locke raises his execute threshold for each sealed champion, for the rest of the game.