[{quoted}](name=Lord Yamazuki,realm=NA,application-id=3ErqAdtq,discussion-id=kAAj1szP,comment-id=000500000000,timestamp=2015-05-12T04:18:50.243+0000)
It doesn't have to be a whole lot, and he would be taking the damage and not it being reduced, also it wouldn't really last as long from what I had in mind. Garen isn't really built as a damage dealer, but a tank with BC. This is why he isn't that good, he has no damage threat, nor cc to really be focused. If Garen ever is buffed, I rather his tanky portion be buffed than his damage.
garen is really damn good if properly built with a mix of damage and defense. he will have enough survivability to get in and assassinate a squishy, get back out, heal up on his passive and get back in.
if youre gonna build him with 4 tank items and cleaver, yea. hes gonna hit like a wet noodle and generally not do anything. ive repeatedly seen tank garens just get chewed up by ad carries, because they outhealed any damage he could do to them. this is now worse than ever with the way the bork passive applies lifesteal with the last patch.
but if you get into a fight with 400 ad, a ghostblade active, a randuin slow, and an infinity edge in your inventory, on 21/9/0 masteries, youre a serious threat. he doesnt have that crit scaling for no reason.
my preferred build at the moment, with variations depending on team comp and opponents of course:

if you switch the maw for a spirit visage, it puts you to cdr cap. (or you could stick with 35% by picking the mastery, or cleaver + inonian boots + the 5% mastery for 40%).
this doesnt just give you a ton of damage and enough survivability to get through a fight, but also a movement speed active on the ghostblade, movement speed on your spin from cleaver, and an aoe slow to stick to people on randuins.
he excells in small skirmishes in 2v2 or 3v3 scenarios. because with a build like this, hes tanky enough to survive the damage of about 3 opponents, while being able to wreck them with his spin, and finishing one off with his ult.
if you build him full on tank, hes going to survive in the midst of the enemy team for a couple of seconds, but hes not going to have any effect.