Blitzcrank is a "sleeper" OP support champion that can change the whole game with just one hook. When played correctly he's the biggest bully in lane. One thing to always keep in mind while playing Blitzcrank is that it is really crucial to land his Q. I'll emphasize this many times more in this guide.

Magic Pen + Ability Power = Surprise Q damage that could result in a flash or an early kill!
Mana regen - Blitzcrank is a very mana hungry champion so that's why it's important to have mana regeneration to help forgive missed pulls.
Armor + magic resist = Good sustainability to go aggressive in lane with Relic Shield to help.

0/9/21 Masteries used for support with lots of utility: Blitzcrank!
Modified with more points for speed boost so you can charge into lane and knock some fools up.

-Best spell LoL hands down. Always pick this to get yourself out of sticky situations.

-Ignite for aggressive laning and quick kills when you land pulls!

-Exhaust is a good choice when going a high burst/high dmg champions/compositions e.g. Talon, Fizz, Zed, Draven

PROS:

Biggest lane bully with his Q
Guarantee easy kills/flash use if land Q early game
Good early invade utility with Q
One hook can change a whole game
E knock up can cancel dash/jumps from enemies prematurely
Sexy hot grill is inside robot suit

CONS:

Mana hungry
VS good opponents a missed pull could be very unforgiving
Almost useless if Q is missed
Q is a bit slow and predictable

Blitzcrank is a strong champion if you land your hooks. If you can't land hooks, W run up to them, E knock up, then Q. (don't do this when you have less than 10% HP vs 2 enemy champions - BE SMART) Landing Q is the most important skill to have for any Blitzcrank fanatic who wants to be the best hooker. Once you master the regular stationary hook. Try to time hooks right when enemy minions die so the enemy can't see it coming fast enough. If you think you're ready to move onto the ultimate level, try a flash-Q combo!

Thanks for reading my Diamond guide on support Blitzcrank. Please rate and comment. Any feedback is welcome!