The point of this is being a full tank while still putting out enough damage to be a threat.

There many directions to go from using the first three items as a base for any build. The reason I like this build is because you're still stacking health for survivability while also gaining AP. It's a bit expensive to get there, but after you get Warmog's, the cash should be rolling in.

After you get a few pieces going, try and get blue. This is amazing for any fights. If your CDR is high enough, you can keep anyone dominated. Add Frozen Heart to this, and you'll be able to control teamfights with ease and probably not even get targeted since the other team will be going after your DPS, but failing because you're raping their faces.

If things are going well, you'll want to go for more health and AP with the items above. If your team is getting their *** kicked, instead of more health, go for team buffs like Aegis or Abyssal specter (or Stark's if your group is melee heavy).

After you get all these items, sell your shield for whatever you need. If you're having problems stacking cash, a good alternative to the Rod of Ages is the sunfire cape.

A potential problem with the health/AP/CDR build is obviously if the other team has good resistances or are also good and CC. In this case, it's okay to abandon AP altogether and just stack resistances.

One of the reasons you may want to stick with the health/ap anyway, is because you'll have to invest a slot into stacking a good resistance item when you can just get health, be more intimidating, and be able to dish out damage. If the other team has high resistances, there's a good chance your stuns wont even work. This is just the safest path imo.

I shouldn't need to tell you how to play. It's all pretty obvious. The only thing I'd mention is to use your ult early if the other team is real bursty with their damage. Use your stuns on the Annies, wait for a few to group, and drop an ult. They will have started their combos 1-2 seconds in, and if you drop it right then, it will screw them up big time.