1. Tyranitar
With the consistent base stats and the strength of a psuedo legend he is number one a gain.
2. Golem
A rock Ball? thats useless, thats what most would say if they heard of a rock ball Pokemon. but Golem is an exception.
3. Onix
Onix was a fan favorite to everyone. He was Brock's favorite pokemon also.
4. Rhyperior
Rhyperior is one of the additions in fourth generation of a regular rhydon turning into an amazing tank.
5. Caracosta
With his dual type Carracosta is helpful against many types.