This build focuses on dealing a lot of damage and having enough health to take damage for your team making him an offtank DPS. You start by buying a Vampiric Scepter, this will synergize well with turtle giving you the ability to solo or duo lane and take the enemy harass skills and out heal them. The key to that though is to be able to hit minions so it would be smart to lane with a lane partner that's a good harasser and a threat to the enemy so you can farm easy. Once you get your lantern you should be destroying minions and gaining plenty of health doing so. It would also be wise to place the ward in the bush next to the river if they have a jungler or a mid that is gank heavy. Once you get to Heart of Gold you should be healthy enough to be able to take a few hits and more if you block with your turtle stance and landing a few hits on the enemy will also threaten them because of Udyr's ability to gain health and block damage its worth it to take damage in order to deal damage to the enemy as long as you aren't putting your self at risk of dying. Late game you should be able to initiate in team fights, deal tons of damage, not die, and due to your utility you can catch people or run away if needed spamming turtle and bear as soon as they come off cool down.

Armor penetration runes, or magic penetration runes are recommended