Hello! I'm Frobei and I've been Challenger multiple sets!
With patch 13.20 bringing many changes, here are the 5 comps that will be strong. I expect the meta to slowly shift before stabilizing around one week later!
BILGEWATER MF REROLL

































This comp was already good in the last patch but it was niche and the mid-game was sometimes tough if you couldn't find your 3 stars easily. Also, Nilah used to be heavily contested and we can expect her to be slightly less contested after the Ionia Vanquisher nerf.
But patch 13.20 brings a significant buff on Nautilus and 5 Bilgewater. Usually, when you reroll for MF and Nautilus you play 5 Bilgewater because it's too hard to find GP at lvl 7. These buffs should make the comp less fragile during the mid-game and help you save HP so you can reroll for your 3 stars.
ZINEDINE ZHERALD (Void Reroll)




























This comp was getting popular during the end of patch 13.19b due to the Chinese meta but it was sometimes lacking a little bit. With the buffs on the Herald we can expect this comp to be much more reliable.
The win conditions of this comp are finding as many 3-star voids as possible (Kassadin and Velkoz are top priority) so augments like Golden Ticket and Frequent Flyers are good. If you can make Reksai 3 then it's a good thing to stuff her properly so she can help Velkoz to clean up the fights.
TF MULTICASTER
























Another comp which was already strong last patch and which receives a significant buff.
The biggest buff here is on Sona who now buffs the attack speed during the whole fight and she also buffs adjacent allies so we don't need to position our carries weirdly anymore. This comp needs to rely on a secondary carry next to TF and it should be either Velkoz or Sona
NOXUS DOMINATION





























Noxus is a dominating comp if you can have a Noxus emblem so you can snowball the early game and get all the Conqueror stacks.
I suggest you play this comp if you can have +1 Noxus OR if you have an early Scoped Weapons to help Mordekaiser gain more range.
KAYLE DEMACIA REROLL




























Another reroll comp that was already strong and got indirectly buffed thanks to Sona's rework.
You should reroll for Kayle and Poppy at lvl 4 and 5 and once you get the 3 stars you can push your levels to 7. At level 7 you will need to see whether you can reroll Quinn 3 / Sona 3 or you can push lvl 9 to get Kayle's final form.
Ideally you do both but that'd be extremely rare unless you get Golden Ticket AND Level Up