Riot Games has unveiled the preview for patch 25.17 for League of Legends. In this update, players will see buffs for Irelia, Vayne, and several other champions, as well as nerfs for Gwen, Master Yi, Rumble, and Singed. Additionally, developers will improve several items and continue preparations for Worlds 2025.

Champion Buffs
Irelia (AP): W AP Ratio: Based on Channel Time: 40% + 20% AP + 50% AP, E CD: 15 → 15, E AP Ratio: 80% → 100%.
Kassadin: Q damage ratio: 60% → 70%, E ratio: 65% → 70%.
Kayn (in lane): Q mana: 50 → 40, W mana: 60-80 → 40-60.
Kog’Maw (AP): Q damage: 80% → 90%, W ratio: 90% → 100%, 1.5% → 200, R AP ratio: 35% → 35%/40%/45%.
Miss Fortune: Base AD: 53 → 55.
Morgana: W minimum seconds damage: 70 → 350 → 90 → 350 W mana: 70 → 130 → 70 → 110.
Nilah: Q attack splash damage to monsters: 10% → 100%.
Senna: AS/v: 2% → 2.6%, Q healing: 40 → 55 → 70 → 85 → 100 → 40% bonus AD → 50% AP, 40 → 60 → 80 → 100 → 120 (+40% bonus AD) (+50% AP)
Sett: E bonus monster damage: 100 → 125-250 by champion level.
Vayne (including jungle): W monster damage: 6% → 10% max HP, capped at 200 → 140 → 200 → always by rank.
Teemo: Mushroom opacity: 30% → 50% (no gameplay impact)

Champion Nerfs
Gwen: Armor: 36 → 33, R initial slow: 60% → 30/45/60%, R Subsequent slow: 25% → 15/20/25%, AS growth: 2.2% → 2.5%.
Master Yi: HP: 669 → 655, Q on-hit ratio: 75% → 65%.
Rumble: P max HP damage: 4% → 3%, Q damage: 60/90/120/150/180 (+100% AP) → 60/85/110/135/160 (+100% AP).
Singed: Poison duration: 2.2s → 2s, Max damage ticks: 9 → 8.

System Buffs
Axiom Arc: Price: 3000 → 2750.
Horizon Focus: Price: 2800 → 2750, AP: 115 → 125.
Profane Hydra: Price: 3200 → 2850, Attack damage: 60 → 55.

Patch 25.17 will serve as a preparatory update before the larger patch 25.18. In it, Riot plans to introduce the first version of anti-boosting and anti-smurfing tools, as well as continue adjusting champions and items for the world patch. These changes will be considered in preparation for Worlds 2025, which will take place in the fall.