Mike and I gave it a shot when they released the rules and cards a while back. Time has muddled my recollection some but a couple things remain.
There are tons of dice. They toned down the BBQ/Fakyeli madness of shooting four different weapons at once, but you still end up with more dice. Existing dust dice or good ol' d6s still work fine with a bit of thought.
Stuff dies quickly and in great numbers. It's not hard to wipe a squad or walker in one activation, even with a tool not suited for the job. More dice plus no armor equals big casualties. Anti-armor weapons will outright kill a trooper, so anti-tank walkers are more effective against infantry. The Wotan is even more deadly.
Command squads are very effective. They have a new action that allows a unit to activate twice, assuming the action succeeds. They can also call in reinforcements, so if your Fireball gets blown up you can bring another one on. They aren't required by the rules anymore, but they're powerful enough that you'll still want one. Or two.
Losing the order phase and the changes to reactions make it feel very different than warfare. I still haven't tried tactics, but I assume it's true to the design intention of tactics without the grid.
Things move and shoot a little further. This doesn't have a huge impact be caused how reactions (don't) work, but the extra movement flexibility is nice.
Picking an army is a mix of 40k and Warmahordes. There are no real limits or requirements, except for heroes still being unique, so you could field nothing but zombies if you wanted to. There are "theme lists" that work more or less like tier lists in Warmahordes. I think Mike ran one but it didn't have much effect. Some look very potent, others are just fluffy. Overall I like the new process. The funky warfare org charts are gone, which is nice, but I worry about spamming the more effective units.
Some of the more obnoxious stuff (read: jump and phasers) got toned down. Lasers are a little more effective. The Wotan in particular is something like 8/1 instead of 2/4. Adding exploding 6s for lasers and no armor makes it very mean and much more reliable. Heavy flaks got better too, not that they needed it, but are also more expensive.
Overall it feels more like 40k with alternating activations than warfare. I think Mike was unimpressed but things went poorly for him. I thought it was ok but couldn't stop noting the differences with warfare. Feels more beer and pretzels now. This isn't necessarily a bad thing, but it's a big change from the tactical depth of warfare. Losing the order phase is unfortunate but not a deal breaker. Effectively losing reactions is a much bigger change that makes me glad I still have my warfare books.
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