I've been grinding the ladder quite well recently (+350LP) and watched the Chinese Mid-Season Finale this weekend. I particularly paid attention to the augments that these top players prioritized and also observed what worked well in my lobbies. So in this thread, I'm making a top augment you should almost always pick and how to play them
Finale Reserves and Medium End Shopping
































These augments guarantee you to hit the Exodia comp with Ahri, Belvelth, and whatever 5 cost units you find.
The only moment when you don't pick medium-end shopping is when you have it at stage 4-2 and you already rolled down previously.
When you hit Final Reserves you want to reach 1 HP when you're already lvl 8 or you won't have enough gold to push lvl 9 AND buy the 5 cost units. However, be careful if someone else also picks this as you might face this person and one of you is going to die.
Noxus Crown































This augment is just way too strong in 2-1 and even stronger IF you plan to play Noxus and you hit this in 3-2 or 4-2. This gives Infinity Edge and Darius next to the Noxus Spat and this is simply WAY TOO STRONG
Juggernaut Crown
































This one is less popular because it requires to play Noxus slightly differently. In fact, you don't push the Noxus tree too much but rather you will want to get 6 Juggernauts.
The damage reduction is way too good and your Katarina, Darius and Aatrox will feel like they are unkillable
Double Trouble and Two Healthy


























Here's the thing, you can win even if only Taliyah is 3 star. It's more important to push your levels to have insane knock up units like Sion, Ksante or Ryze in Targon/Shurima portals rather than staying stuck lvl 6 to find Sett 3. DO NOT HESITATE to give up Sett 3 once you found Taliyah 3 to get this very late game board.
The prismatic version of Double Trouble is less interesting than the gold version but it's still good
Riftwalk Kassadin






























Riftwalk makes your Kassadin a MONSTER but you have to pick it only at stage 2-1 and only if you have good components for him (at least one glove + rod or tear). You will reroll Kassadin at lvl 6 and if you can make Soraka 3 as well. However, it's just like Sett in the DT setup, you really want to push your levels to find Ksante and have 6 bastion ASAP
Ravenous Hunter































Similar to Riftwalk, it transforms your WW into a monster. With the last buff to 4 Juggernauts, it becomes more interesting to go for the 4 chall + 4 jugger. It's a comp you want to reroll at lvl 6 and you're not obliged to have Sett 3
Gargantuan's Resolve



























For some reasons this augment was an instant pick in China. I believe they have a very strong 3 cost meta and this item augment is simply insane in the Noxus setup. It's also great in a Reksai setup even though I don't consider Reksai at the same level as Darius.
You already have the Noxus setup above so here I give you the Reksai setup
Glacial Breeze

Freljord is becoming very meta because it's an excellent synergy to play Deadeye or Gunner but it's also good in many other setups like Invoker for instance. This augment simply makes the setup on a whole another level for Aphelios and Zeri (protection + AS). It's not an augment I'd pick at stage 2-1 but rather at stage 4-2 when I already have Freljord on the board.