Swain

The passive pulls enemies CC'd by your allies — coordinate with your support for pull + burst.

R (Demonic Ascension) drains nearby enemies in AoE — activate it and stay in the middle of the fight. Zhonya's during R is very effective.

W (Vision of Empire) has global range — use it to spot enemies, assist ganks, or check bushes from a distance.

E (Nevermove) comes back toward you and roots — the root triggers on the return, not on the way out.

Stay out of his R drain range — if you can't burst him, back off and wait for R to expire.

His E root triggers on the RETURN: dodge the returning projectile, not the outgoing one.

Grievous Wounds reduces his R drain and passive heals — buy it early.

Swain is vulnerable to long-range champions who can poke him without entering his drain zone.