Hello, I have just began testing shen on 3v3 and do not know how i feel about him. Should i be building ap or just health? In 3v3 he can be very powerful but he seems like he doesnt contribute to much in team fights. Can i get some peoples opinions on how viable shen is in 3v3 and also what is best build?

You should play him a mix of disruption and tank. Items like Iceborn Gauntlet, Randuins Omen, and Sunfire Cape help keep him really tanky and add to his contributions in teamfights. His passive, Q and E will help add a bit of damage and help keep your carry safe. I havn't ever experimented with building him ap, if I want damage on him I go for items like Iceborn, Trinity Force and Statik Shiv.

OK thanks for the advice, but iceborn gauntlet on shen? Wouldnt that be a waste of money as I am spending extra for the useless +500 mana. In theory it sounds goodd, il test and come back with results. Any more help would be greatly appreciated.

Iceborn is a pretty situational item (I was rattling off my common items, I just find Iceborn incredibly, trollishly fun) for when your taunt just isnt enough cc. Typically if our team is doing well when Im Shen I will get an early Sheen to give his damage a boost (his passive + Sheen has insane burst for the early levels). About the wasted mana on Iceborn, I feel that its armor and actives more than make up for not being 100% efficient on Shen.

In a standard game I will go for either Randuins or Sunfire first (Randuins if they have an aa based carry like ad Yi or Vi; Sunfire if they have an ability based champ like Darius or Riven [the reasoning is Sunfire is cheaper and you can get it faster and it adds some potency to just having Shen in the fight; ability based ad champs tend to be more burst than sustained). After that I'll start getting the items for Trinity then vary my build based on need. Frozen Mallet gives you tons of hp and great single target chasing. Static Shiv really adds to your dps output and mobility, allowing you to land those crucial taunts or get away clean from a bad fight. Iceborn Gauntlet gives you more armor and a persistent aoe slow which is a great way to soft-counter teams that rely on sticking together and their kiting abilities to stay strong.

It's pretty rare that my build order for Shen stays persistent from game to game. As the teams main tank you need to be adapting to each game, not just following a practiced design.

get either mercs/ninja tabi, rush sunfire if they have 2 ad, or rush qss if they have double ap, Then from there build health. you'll do fine, IMO atleast go for 9/21/0 get magic pen or armor pen deciding which you prefer, and you'll do fine. I hardly use shen on 3s, since all he brings is taunt to the table, I found rammus works much better for 3s then shen.