This build is great if you are solo-tanking.

You have to be aggressive, and yet careful.

Keep your Q off-cooldown for escapes (and to charge-heal yourself to full, while avoiding 95% of all CC), unless you are confident enough to Dash back into the fight and finish off a hero. W should be on cooldown, and should always be used on 1 Hero and several other enemy minions or structures at a time. Constantly bombard the enemy structures with E, hopefully catching heros in its path. Escape sticky situations with Hammer of Twilight, or engage with Hammer at level 20.

This build is geared towards sieging, and is best used when you have a tank, and a high-sustain or 2 bursters.

On maps with close lanes, minion-objectives, and/or lots of camp respawns... you can't go wrong with this build.

Stack up your W, avoid close-quarters fights (poking with E), and Q ONLY to escape and become Unstoppable.

Use Upheaval when Gall has heroic, and team is ready for follow-up. Immediately move your body in a defensive or offensive position, and hit your Molten Block to prevent ALL CC, also dealing a good chunk of health from your decimated enemies.