Kayn vs Sylas Jungle Matchup

Kayn Jungle wins 52.1% of 4,991 Low Elo games against Sylas Jungle, +0.7 points vs expected, 2-patch window 26.19-26.20.

Researched on LoL patch 26.20. Tips are written to hold at any rank; stats come from Low Elo ranked games up to patch 26.20.

How to play as Kayn

Before Rhaast is available, ward and track Sylas so you can path away from his early invade; players report that he can kill Kayn before form if he finds him. (Unverified: no source confirms this note.)

Once Rhaast is unlocked, use the form's sustain to contest the duel instead of giving Sylas uncontested control of your jungle. (Unverified: no source confirms this note.)

Sylas's Kingslayer(W) heals him, while Rhaast heals from spell damage to champions, so a duel after Kayn's transformation can become a sustain fight.

How to play as Sylas

Invade while Kayn is still base form, but avoid forcing a straight duel after he becomes Rhaast unless you have a lead. (Unverified: no source confirms this note.)

Sources

These notes come from r/KaynMains, checked against the champions' abilities.