From its description in the store, it sounds pretty close to a plasma cannon; can shoot anti-armour or high-explosive shells to deal with "cowards hiding behind cover" (so probably in a low arc?), or an alternate mortar fire. I. Need. More. Info. NAOW!
People have and it seems to work like a plasma cannon but without the plasma. I don't have it though.
Yes I got it last night. Hooo boy is it fun*. It has 2 firing modes, each of which has an uncharged and a charged shot though I'm not sure if there's a difference between the 2 uncharged shots. But it totals 3 different firing options. Word to the wise, it has to reload after each shot. #1 - A grenade launcher that launches the standard frag grenade. They bounce around all over the place. In the garrison they do about 260-ish damage. #2 - Essentially a bigger better rocket. It takes about a full second to charge, then goes in a straight line and pretty fast especially for a projectile like weapon. It deals about 800 damage on a full hit. and to my knowledge goes directly where the reticle is pointed. It has a fairly big splash effect. It kills vehicles in about 4-5 shots. #3 - Mortar. It's pretty similar to #2 but it has a "projectile path" similar to the plasma weapons and it goes up at about an angle of 45 degrees. It also takes about a full second to charge and deals 800 damage. I feel like this mode has a larger splash effect but I haven't actually tested it yet. Definitely a must have for defending Harkus or any vehicle heavy maps. I think of it like a Zzap gun that can actually deal with infantry as well. But you WILL kill friendlies with this weapon. A lot of them.
So it *is* a plasma cannon, then, noted. Damn, this sounds awesome, I need it. I'm still only at... a bit more than 7k Req I think.
Deff Kannon Loota Nob here. Shits great. The projectile is about 2x-3x faster than a plasma cannon projectile. The trajectory arc is a bit wonky and the projectile has a habit of randomly flying in a direction or seemingly doing no damage in mortar mode, but man when it hits? It hits hard. It's swiftly growing into my favorite weapon just for hilarity and the fact that it punches holes in predators and rhinos without a jonky windup like the lazz kannon. Prepare to be focused though, CSM and SM are utterly terrified of an ork with a Deff Kannon and will focus the hell out of you. In fact the only con I have with this weapon is that it can't be reloaded while braced. Gets annoying when you have to back off, reload, and brace again to get a stable mortar shot.
Yeah, it really needs to reload while braced. That's the only thing keeping it from being a top tier weapon. That, and the little grenades have a bit too much bounce, so you can't land it at anyone's feet. The fact that it bounces is fine, but I often see it skidding along the ground way past the target. Should be a bit more like Junkrat's gun from Overwatch or the Demo guy's grenade launcher from TF2.