Fizz vs Lillia

Last-hit minions with Seastone Trident (W) early on: if the empowered auto kills, you get mana back and its cooldown drops.

Save Playful (E) to dodge a key spell: you're untargetable for 0.75 seconds, then land with damage and a slow.

Cast Chum the Waters (R) from range: the farther the fish travels before it attaches, the stronger the shark's slow and damage.

After Chum the Waters (R), chain Urchin Strike (Q) and Seastone Trident (W) while the target is slowed: the shark then bursts up under them and knocks them into the air.

Against Blooming Blows (Q), stick to her or back out of range: only the outer edge of the zone adds true damage.

Get out of the center of Watch Out! Eep! (W): the zone deals much more damage there than at the edge.

Dodge her spells, even Swirlseed (E), which rolls to the first enemy: each one marks you for Lilting Lullaby (R), which puts every marked enemy to sleep.

If you have CC, use it on her: with no dash, she relies on the move speed Blooming Blows (Q) gives her for each spell that hits.