That's not even the biggest Titan class either. To use a BT comparison, the Imperator-class makes the Warlord look like a Wasp against an Atlas.
Back when i ran a Games Workshop store, we had a guy bring in his scratchbuilt 40k-scale Imperator. It was 5 feet tall.
we used it in the big 4 table battle we ran, each table was a different part of the larger battle, one was an assault on imperial artillery batteries, one was the battle for the city walls, one was a fight in the sewers (we had a space hulk table) and one was a battle for a communications relay on a moon. The people who controlled the comm relay could call in strikes from the Imperator, as long as it was functioning. We also had a fight going on on the imperator itself, around the castle on its shoulders. It was really cool, one of my proudest moments putting that event all together.
A fight for control of the Titan, while it is raining down The Emperor's Judgement on heretics on another table. That does indeed sound quite fun.
I've done a ton of titan class battles with Apocalypse formations in 5th edition warhammer 40k. They make for fun games. Apoc balances out at about 6500 points a side. Biggest game yet was 18,500 points a side and we used half a school gym floor to play. It took 3 days to finish up. We had 14 players total. This was back in 2nd edition when armorcast made a warlord class ork gargant This was the cover to the Epic scale warhammer 40k Here's some fun stuff to look at: Imperator class titan Emporer class titan (Chaos) Phantom class Eldar titan (the model at the bottom is a regular scale dire avenger) and Revanent class Eldar titan beside a Warhound class Imperial titan
To be frank: Those pics are fucking tit milk. Glad I didn't get into WH40k now. I would've spent sooooooo much money on stuff like that.