10k points Apocalypse Game

A part of the "Arata-mi Tatele" team visited Oradea for a massive 10.000 points game.
I brought a 4000 points army consisting of 18 models. I had 3 titans, 2 primarchs and some batteries.
Our Necron brought a Tesseract Vault and 3 Doomsday Arks.
The Tyranid player brought a ton of Genestealers.
 We played against T'au, Necrons and two Imperial Guards.  Unfortunately for us, our opponents brought a million foot soldiers.
Deployment took and hour and a half and our first turn took 3 hours.

After the second turn we cleared about half of the Imperial Guard and a big chunk of the Necrons, but we lost almost all of my army, more than half of the Necrons.

After turn 3 we stopped the game, we had to head back home. We played for 10 hours and we won the game 5 - 4. If the game would have continued we would have surely lost.
It's an absolute horror to play against so much infantry. They were blocking everything, we were killing but they kept coming.