Blitzcrank, is a GREAT offtank, if you build DPS and Mana like this build will explain, then you will have 2k hp plus all the bonus mana, putting it in the 2-3k range, I main with Blitzcrank and always become an incredible destroyer, so please enjoy.

With my Runes, I normally build AS Marks and Quints, I build Magic Resist Glyphs, and AD/Armor Seals, the AD Seals are kinda pointless, but they are always nice to add. These Runes allow me to constantly smash with my AS and the Magic Resist and Armor allow me to stay in the fight a little longer, while

The Masteries are great for the AD boost, and the survivability that the Defensive field gives you, then the Utility gives you a little less death time and some Regen on MP and HP.

The Items are vital for him due to the fact, that MANA is Blitzcrank's savior, Mana makes his passive shield give him a second life basically. Then HE IS AN AD CHAMPION, His Power Fist and Overdrive is to Autoattack and kill them, along with a 30 sec CD ult, So thats why I build AD and Mana early game, allowing me to kill easily, and then later on, you want to build survivability, so you can Kill and Live.

I chose that Skill Sequence due to the point of grabbing them and Power Fisting can do alot of AD, and the Overdrive doesn't need to have alot of skill points in it, to be able to escape and do alot of punchs, along with my AS runes.

Heal is great for early game 2v2s, before the minions come, if you guys fight in the lane (which you probably will) before the minions come, then if it is a close fight and you and your lane partner are going to die/lose, heal can give the extra 100-200 hp that is needed in order to turn the fight around and win. Teleport is great for Blitzcrank because he is a VERY SLOW champion, with a Movespeed of only 300 at level 1, so it would be great to stay in the lane alot.

In general, Bltzcrank is a great offtank and a great champion for his survivability, very unique pull, and amazing AD, so that is why I like him and main with him, Viva la Blitzcrank!