Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
1. Powerball makes you go ZOOOOOOM into the other team.
2. Then your taunt lets you have your way with whom ever you want.
3. Defensive Curl is like OMG FU damage.
4. Ult is zomg stay away from the person im having my way with.
This build focuses on TANKING. If Rammus thinks he can do damage tell him to GTFO. Hold a person still while your team kills. That's the name of the game.