Hello summoners patch 10.15 is here! Lets go over those changes!

Skins: Spirt blossom is here and here are the champions who are getting skins:
Lillia, Yasuo, Riven, Vayne, Ahri, Cassiopeia, Kindred, Teemo and Thresh. This patch also introduces us to Prestige Teemo.

Runes:
Unsealed Spell book: Cool down increased from 240s to 300s
Cooldown reduction per spell increased from 20s to 25s

Items:
Spellthiefs Edge: Mana regen increased from 25% to 50%
Frost Fang: Mana regen increased from 50% to 75%
Shard of True Ice: AP increased from 45AP to 50AP

Champions:
Introduction: Lillia (To learn more about Lillia click here)

Buffs: Caitlyn, Gragas, Irelia, Rakan, Shen, Skarner, Swain, Yuumi
Nerfs: Aphelios, Fiddlesticks, Lee Sin, Ornn, Thresh, Twisted Fate

Buffs:
Caitlyn:
Base attack damage buffed from 62AD to 64AD
Base movement speed buffed from 325 to 330

Gragas:
W- Drunken Rage: Damage ratio is 0.5AP to now 0.6
R- Explosive Cask: Damage ratio is 0.7AP to now 0.8

Irelia:
Passive-Ionian Fervor: Bonus attack speed per stack is going from 60% at 5 stack to now 80% at 5 stacks

Rakan:
Passive-Fey Feathers: Cooldown reduction of 1.5 seconds per LvL

Shen:
Passive-Ki Barrier: Shield value of 101 is now buffed to 121

Skarner:
Q- Crystal Slash: No longer deals a flat amount of damage, it now deals 15% of your total AD and 3% of your targets max HP. Is now on a 5s cool down and costs 15 mana through all LvLs
E- Fracture: Removed “Keep it moving”: Missiles no longer losses travel speed after hitting an enemy champion

Swain:
Passive- Ravenous Flock: Now has a 10s cool down for all ranks (but can change with CDR items). No longer grants him mana when birds come back
Q- Deaths Hand: Cooldown is going from 4s to now 3s
W- Vision of Empire: Range is now 7500 from 3500, Damage is now 240 from 300, and mana cost is now 110 from 130
E- Nevermore: 10s Cool down at all ranks and lvls and now a 50 mana from 60

Yuumi:
Passive- Bop n Block: No longer restores 160 mana, now restores 100 mana + 8% max mana and cooldown is going from 8s to 6s

Nerfs:

Aphelios:
Q- Crescendum, The Chakram:
Sentry range: is now 500 from 575
Q – Infernum, The Flamethrower:
Removed the ability to use “Runaan’s Hurricane” to get more missiles.
Missile Count: now 6 from 8
R- Moonlight Vigil: No longer deals damage without going on cooldown if Aphelios is killed during the ability’s cast

Fiddelsticks:
W- Bountiful Harvest: Healing nerfed to 15% against minions from 25%

Lee Sin:
W- Safeguard: Cooldown is now 14s from 12s

Ornn:
Base Armor: is nerfed from 36 to now 33

Thresh:
W- Dark Passage: Cooldown is nerfed to 16s from 12s

Twisted Fate:
W- Pick a Card: Cooldown is now starts at 8s and lowers to 6s at LVL 18, is no longer a 6s cooldown at all ranks

Now lets move onto the champion tier list
(Collective information from Challenger Replays, OP.GG, Myself, League of Legends, and ProGuides)

Toplane-
OP Tier: Darius and Quinn
S Tier: Fiora, Garen, Volibear, Kled, Jax, Urgot, Nasus, Singed, Shen, Camille, Riven
A Tier: Wukong, Sett, Renekton, Malphite, Poppy, Swain, Vlad, Rengar, Illoai, Irelia, Soraka, Vayne, Teemo, Tyrndamere, Hecarim, Kayle
B Tier: Gnar, Pantheon, Sion, Yorick, Kennen, Jayce, Rumble, Gangplank, Sylas, Neeko, Kalista, Yasuo, Lucian, Ornn, Mordekaiser, Nautilus, Karma, Skarner
C Tier: Aatrox, Dr. Mundo, Zac, Cho’Gath, Ryze
D Tier: Kayn, Akali

Jungle-
OP Tier: Karthus, Kha’Zix
S Tier: Fiddlesticks, Volibear, (Full AP) Nunu, Lee Sin, Rek’Sai, Shaco, Elise, Warwick, Kayn, Evelynn, Nidalee, Wukong, Zac, Graves
A Tier: Kindred, Ekko, (AP) Shyvanna, Hecarim, Rengar, Ramus, Master Yi, Xin Zhao, Vi, Sejuani, Skarner, (Lillia?)
B Tier: (Full AP) Amumu, Nocturne, Taliyah, Gragas, Diana, Morgana, Ivern, Dr. Mundo, Udyr, Jarven IV, Trundle, Twtich
C Tier: Pantheon, Mordekaiser, Sett, Sylas, Zyra
D Tier: Camille, Qiyana, Talon, Darius, Garen, Brand, Teemo

Midlane:
OP Tier: Kassadin, Fizz, Cassiopeia, Kai’Sa (Swain?)
S Tier: Vlad, Zed, Talon, Katarina, Ekko, Diana, Sylas, Annie, Karthus, Yasuo, LeBlanc, Zoe, Syndra
A Tier: Galio, Twisted Fate, Ahri, Malzahar, Qiyana, Orianna, Neeko, Lux, Irelia, Viktor, Aurelion Sol, Kayle, Azir, (Lillia?)
C Tier: Ziggs, Corki, Karma, (Glacial Aug) Cho’Gath, Ornn, Sett, (Glacial Aug) Morgana, Akali, (Glacial Aug) Kog’Maw
D Tier: Malphite, Brand

Botlane- (ADC) (Manamune & Death’s Dance are now MANDATORY items on some ADCs and will be labeled with a “MD” next to their name for this change)
OP Tier: MD Ashe, MD Kai’Sa
S Tier: MD Vayne, Caitlyn, MD Jinx, Jhin, MD Draven, MD Ezreal
A Tier: MD Ahpelios, Cassiopeia, Taliyah, (Healer) Senna, Ziggs, MD Miss Fortune
B Tier: Heimerdinger, Twitch, MD Kog’Maw, MD Tristana, MD Lucian
C Tier: MD Kalista, (Leth) Varus
D Tier: MD Xayah & Xayah, Corki

Botlane- (Support)
OP Tier: Lulu, Yuumi, Soraka, Nami, Janna, Sona, Senna
S Tier: Rakan, Alistar, Karma, Bard, Blitzcrank, Thresh, Nautilus, Morgana, Leona
A Tier: Zilean, Pyke, Zyra, Brand, Taric, Galio
B Tier: Vel’Koz, Shaco, Braum, Lux, Fiddlesticks
C Tier: Xerath, Veigar
D Tier: Gragas, Shen, Tahm Kench, Poppy, Volibear

And now for the best runes and items in patch 10.15:
Glacial Augment
Dark Harvest
Conqueror

Death’s Dance & Manamune