Lillia vs Zac Jungle Matchup
Lillia Jungle wins 54.2% of 1,269 Low Elo games against Zac Jungle, +1.2 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.
Why Lillia is favored
Lillia's movement speed from Blooming Blows(Q) lets her space Zac's Q and E, and her passive burns a percentage of his health if he cannot reach her. Zac's players point out that he needs teammates to follow up on his crowd control; the matchup is harder for him when Lillia can keep the fight at range.
Measured in High Elo: Lillia wins 2.2pp more often than expected over 1,056 games.
How to play as Lillia
Keep Q movement-speed stacks when approaching Zac and use them to sidestep his Q or E; if his engage lands and allies can follow, back off instead of turning the skirmish alone.
Zac's Q and E can start a crowd-control chain when allies are nearby, while Blooming Blows(Q) grants Lillia stacking movement speed that helps her kite if she avoids the initial engage.
Dream-Laden Bough(P) deals additional max-health damage over time when Lillia hits Zac with a skill, so repeated spells can wear down his tank health.
How to play as Zac
Look for ganks with an ally ready to follow up on Q or E; Lillia can sidestep an isolated engage once her movement speed is stacked.
Sources
These notes come from r/LilliaMains, checked against the champions' abilities.