The new UNSC Kestrel floating ship (which was intended for but cut from Halo 2) provides a bit more firepower than the Warthog with a tad less speed. Having the straightforward UNSC pistol and dual semi-automatics, the Convenant's more complex Needler, and the Promethian's powerful-yet-slow incineration cannon available on the same level allowed for more combat variety than I've seen in most twin-stick shooters. There's a bit of repetition between human, Covenant, and Promethian weaponry (a fact that’s tougher to bear when they're millimeters apart on the ground and represented by tiny icons) but having the majority of Halo's artillery at my disposal was worth it. There's also a few great combat options you can pluck from those Promethian corpses, including the scattershot gun and the shock chain ability that makes some of the late-game onslaughts a bit easier to tackle. Due to ammo limitations, Spartan Strike already encourages a more tactical-top down action experience than most typical twin-stick arcade-style shooters, but having to reassess an otherwise benign enemy that revives the heaviest hitters made for some of my favorite sequences particularly when I had to manage another element like an NPC to guard or a gate to slowly open. In particular, the Watchers add a nice twist with their ability to revive Spartan Strike's two toughest enemies: Knights and Promethian turrets. At around the halfway mark though, Spartan Strike gets really interesting with the incorporation of Halo 4's Promethian enemies and weapons. Besides an improved reticule system that makes aiming a tad easier, I was using most of the same weapons to mow down most of the same enemies,though the stages aren't as one-note as they were before. The first few levels of Spartan Strike seem almost like a post-patch Spartan Assault.
While I was initially irked by Spartan Strike's non-canon status, it uses this “what if” scenario to really open up some combat diversity, it just takes a little time getting there. Like 2013's Halo: Spartan Assault, Spartan Strike takes place within a tactical simulator, using fictional combat situations to train soldiers.