Steamrolling is the use of overwhelming force to decimate an opponents. This tried and true tactic is perfect for taking out opponents bases, no matter how well they are defended.
The Mammoth Tank is the best steamrolling unit. Its cannons (railguns once upgraded) can easily shred through vehicles and infantry alike. Along with its 2 SAM launchers and Anti-armor missiles can counter any opponent counterattack.
The MARV is also effective, but it does not do a huge amount damage with its tri cannons because it is meant for turning Red Zones into Blue Zones.
The GDI has the newest Mastodon walker and the newest Mammoth Tank for steamrolling purposes.
The Avatar is Nods most powerful unit. Best used when flanked by Saboteurs (to recover them, but if they don't get killed), this allows a commander to constantly use the same weapons over and over.
What is worst, is that Purifiers are the same thing. Only it is very different and dreaded. Even Mammoth Tanks fear its flamethrower, and Commandos cant even get close enough to do damage to it.
Redeemers do not make much cash, but it is quite strong and can turn anything on the ground against each other with the Rage generator.
The Avatar in Tiberian Twilight has many cannons for delivering punishment to the Avatars enemies.
The Annihilator Tripod is the Scrin's steamrolling unit. It's 3 cannons can easily shred defenses, and can be combined with buzzers and a shield.
Also the Reaper Tripod is another alternative along with huge building sized Eradicators.