The boots at the beginning are to insure that you can catch the runner from opening gank. With the build I'm using u can get out of the base at under 15 seconds. The three health potions help you stay in the lane for a long time early game, mixed with your passive. Boots of swiftness are meant to sync with your Q. I rush phage next, getting the long sword before the ruby crystal, just for the burst damage. Then i continue onto frozen mallet, because it not only makes you hit like a truck, but it also slows your opponents with every hit, so you can chase very well. Next is sunfire cape, for the obvious sync with Judgment, since it is Garens main damage output. Then comes Atma's Impaler, for the damage and the critical strike makes Judgment do more damage, since it scales with critical strike. That being said, the reason for the two Avarice Blades is quite obvious. The sunfire cape, frozen mallet, and armor from Atma's makes Garen quite tanky, yet he still can do incredible amounts of damage.