Centurions take up power-walking

Time for white scars!

The drawback of Centurions was their slow speed and short range, and getting them into a good position early on was difficult.
This can be solved with a healthy application of Scout.

This starts off with White Scars being the primary army, as we need Khan to be the warlord. He will of course be rocking his pimped out bicycle.
This unlocks two things: First is 5-man bike squads are troops, always a good choice. But more importantly, he gives Scout to models on bikes, which includes Khan himself.

Next are some actual bikes, as we want to build an army true to the fluff...
5 Squads of 5 bikes should, do all with 2 grav guns and a combi-grav. After careful consideration, there are only a few cases where plasma is better than grav, all other times it's best just to stack more ap2 shots.

To round it off, a Storm Talon.

Next come the allies. Which will be more Space Marines, Ultramarines.
The grand toolbox himself makes an appearance, Tiggy. He can still be a bit of a double-edged crutch, but we have a few other tricks now just in case he screws up and brings the Ikea coffee table assembly instructions instead of the correct divination scrolls to battle again.

For troops, 5 Scouts make a brave appearance, sporting a single melta bomb.

Another Storm Talon, which make use of Tiggy's reserves reroll, giving us some light anti-air, and general supporting fire.

And now the actual important part, 6 Centurions.


The trick is to join Tiggy and Khan onto the Centurions during deployment, so now the entire unit can scout thanks to Khan's bicycle.
This is enough to get them onto the half way line in turn 1, and now they can start shooting away at things all game.
As they are still Ultramarines, they still get all the nice combat doctrine bonuses, in addition to scout.
All the other Scouting bikes and grav make for a nice first turn strike against an unprepared army, and having so much mobility around a central firebase is quite advantageous.

The white scars Storm Talon escort the scouts in reserve, so now both planes get to make use of Tiggy's rerolls.

So, the list looks like this:

Khan: Moonbicycle
5 Bikes: 2 Grav Guns, Combi-Grav
5 Bikes: 2 Grav Guns, Combi-Grav
5 Bikes: 2 Grav Guns, Combi-Grav
5 Bikes: 2 Grav Guns, Combi-Grav
5 Bikes: 2 Grav Guns, Combi-Grav
Storm Talon: Skyhammer Missiles

Tiggy
5 Scouts: Melta Bomb
Storm Talon: Skyhammer Missiles
6 Centurions: Grav-Cannons, Omni Scope


That looks to be an adequate amount of magic gravity bullets.
The one major downside to the list is that there aren't actually many troops, and the bikes can be surprisingly squishy. Keeping them safe in reserve means less firepower, although so many outflanking units does have it's benefits.
The main thing is that everything is much more mobile than the previous iteration.