It’s been a while since we checked in on Army of Two: The 40th Day, and from what we’ve seen it appears to be progressing nicely. At a recent event hosted by EA in Tokyo, we had a chance to get our hands on the game and explore the revamped weapon customization system.

Benoit Richer, Level Design Director, demoed the game while two EA staffers played co-op via a vertical split screen. The scene, which we were told took place early in the game, unfolded in an industrial area at night. Little was divulged about the story, other than the main antagonist is named Jonah. Jonah has a vision for Shanghai, and it’s not in line with how the metropolis currently stands. So he and his army, dubbed The 40th Day Initiative, will rebuild the city as he envisions it—after leveling it with little care for inhabitants. Salem and Rios appear to be in the wrong place at the wrong time.

Immediately upon the start of the demo the duo were presented with a moral decision. Members of The 40th Day Initiative held several civilians hostage. Salem and Rios could mow down everyone indiscriminately, or they could each tag a baddie before carefully taking them out. The EA staffers opted for the latter, counting down out loud before taking the foes out in tandem, leaving the civilians unscathed.

As they progressed further in the level and into a sprawling metal courtyard, teamwork became more important. Surrounded by troops, the real-life team communicated enemy locations, once even teaming up behind a riot shield to gain ground quickly. This is when we noticed that the Aggro system has been toned down somewhat, now a slight blue glow instead of the blazing red aura.

During this battle we were introduced to the first of several heavy unit types. Each heavy unit is introduced in a manner that makes their weakness somewhat obvious. The Heavy Shotgun unit carelessly left his head uncovered, making him relatively easy to take out if you can avoid his deadly blast area.

After the demo, we sat down with Richer to chat about new features and get our hands on the game. While he couldn’t talk much about the morality system and how it will affect gameplay, he did confirm that doing good deeds (saving hostages and so on) will result in rewards such as cold cash or weapons parts. Richer couldn’t speak on the pros of taking an amoral path, other than that availability of some missions depends on your moral alignment.

Weapon customization was the most impressive aspect of the demo. In the original Army of Two players would bank cash to upgrade their stock, barrel and magazine. Or to bling out their gun in gold. This time around the customization is nearly limitless. Now you can swap out the barrel, cartridge, stock, suppressor, scope and front mount of any weapon with any other weapon in your inventory. The team is intentionally allowing individuals to create guns outside the constraints of reality, wanting to make the feature hardcore without sacrificing the fun of creating your own unique weapon. Richer referred to their philosophy as “Legos meets guns.”

As before, you can also change the style of your selected firearm. This time you can coat your weapon in gold, jungle motif or zebra print, along with dozens upon dozens of other options. Front mounts have also become more creative, allowing you to attach found items like a screwdriver or a kitchen knife. Picked up a discarded Coke can? Use it for a silencer? Over 8000 custom guns can be crafted in the new title. That’s quite an upgrade from the original mechanic.

We asked about multiplayer, but were told that they weren’t quite ready to talk about it yet, with more details set to debut in October.

Army of Two: The 40th Day will hit retail shelves in North America January of 2010.