Lissandra vs Locke

Cast Ice Shard (Q) through a minion: the spear shatters on it, and its shards damage and slow the champion behind.

Engage from the flank with Glacial Path (E): recast it to blink to the claw, then root nearby enemies with Ring of Frost (W).

If you're getting focused, cast Frozen Tomb (R) on yourself: you become untargetable for a moment, heal based on your missing health, and the ice slows enemies around you.

Stay in the heart of teamfights: Iceborn Subjugation (passive) turns an enemy champion who dies near you into a Frozen Thrall, which slows, then explodes.

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.