I have been enamored with this unit since I first decided to do a Death Guard Legion.
So a little breakdown on the unit. A Grave Warden Terminator Squad is a Heavy Support Choice in a Death Guard Legion list.
These guys come stock with Cataphractii Terminator Armour, Assault Grenade launcher, Power fist and Death Cloud. You can add chain fists, 1 heavy flamer per 5 models, and the sergeant has access to combi weapons.
Being a Heavy Support Choice doesn't hurt, as they can take a Land Raider or a Spartan as a transport option, making it a double tap on Heavy Options, although either choice is expensive (cost and points)
The assault grenade launcher is an interesting concept. I like the krak option since its a STR 6 AP 4 Assault 2. The other round option is Toxin grenades, Toughness test, AP4 with no cover saves. Lots of close ranged hurt sauce going out. Good against mass, light armored troops, but not great against T4 Power Armored Marines.
Now Death Cloud is where this unit gets their interesting rules. This unit now can become a sort of counter charge unit since a unit that charges them will not get their +1 attack on the charge and they count as charging across dangerous terrain. Has the same rules as the toxin grenades above.
So, battle plan is to Krak grenade anthing that moves, and use them as a charge defense, with Toxin and overwatch.
Fluff wise these guys nail what I think the Death Guard are about.
Onto the sample model. Unfortunately, every picture white washed out the models helmet, but in real life, this model has it going on.
Tonight, as I am working on his 4 squadmates, I will work up a tutorial to post tomorrow.