Garen vs Gangplank Top Matchup
Garen Top wins 50.5% of 2,565 Low Elo games against Gangplank Top, -0.6 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 Garen
Do not trade health for every minion while Gangplank is poking with Parrrley(Q). Farm within experience range, recover with Perseverance(P), and wait for a safer all-in window.
Treat each keg as a timing contest: Garen can use an attack followed by Decisive Strike(Q) to contest it quickly, while Gangplank should place barrels where Garen cannot safely reach them.
Decisive Strike(Q) resets Garen's basic attack, letting him hit a Powder Keg(E) twice in quick succession during the barrel timing contest.
Powder Keg(E) slows Garen when it explodes, but Decisive Strike(Q) can clear the slow and help him keep moving.
Sources
These notes come from r/GarenMains and r/gangplankmains, checked against the champions' abilities.