Final Composition
Legends
Twisted Fate - Gives access to Pandora's Box/Pandora's Items II which allow us to hit Garen's Best items and then make more Zeke's Heralds.
Master Yi - Pumping up is a great augment for this comp as you want Garen to have as much attack speed as possible.
Vladimir - provides a selection of good combat augments, one of these being ascension which is good as we want extended fights.
Lee Sin - Great for any re roll comp.
Augments
Pandora's Box
Pandora's Items II
Adrenaline Rush
Pumping Up
Ascension
Juggernaut Crest/Heart/Crown
Gargantuan Resolve
Blood Price
Early Game
You want to play your strongest board early until you hit level 7, above is just an example of we were to hit an early Garen. Kayle is a good item holder for Garen and is also a Demacian unit so this will allow you to have an early 3 Demacia with the addition of Poppy.
Another variation would be if you hit Sett and Warwick early. Jhin would be the item holder in this example below:
Mid Game
You want to try to maximise your econ until you hit level 7 and then you can slow roll for Garen 3. Pick up any Darius you hit on the way but don't if it will harm your econ.
Piltover is really good to run in the early/mid if you can hit it. Otherwise you can just play strongest board, another example below.
Late Game
Once you hit garen 3 you need to econ back up and level to 8 to look for Aatrox, Nasus and Aphelios.
