The less said about the story in Advance Wars: Days of Ruin, the better. Basically, Intelligent Systems and Nintendo abandoned their goofy, kiddie take on warfare in favor of a bleak, joyless romp through a post-apocalyptic wreck of a world. It’s as if the series has grown from a bright, enthusiastic kid into an angsty, melodramatic tweener. I’m terrified to see what will happen a couple of installments from now, when Advance Wars wants to start dating and get its driver’s license.

Even more disappointing are the characters. The problem isn’t just that they’re bland and underdeveloped, it’s that they no longer feel integrated with the gameplay. The old COs came with strengths and weaknesses that matched their looks and personalities: laid-back Grit would hang back and hold you off with long-range artillery; proud Kanbei’s expensive but powerful units made every battle feel like a heroic last stand. In Days of Ruin, I can’t be bothered to remember any of the characters’ names, and the distribution of strengths and weaknesses goes back to being just a numbers game, rather than an expression of personality or a way of amping up the dramatic arc of a battle.

Even though the characters and story are so lackluster, I’m still pouring much more of my time than is healthy into Days of Ruin, because the gameplay has gotten deeper. Some of the new units are more interesting than others: carriers are sexy, but expensive and brittle; bikes quicken the early land-grab phase; flares make artillery twice as effective in fog of war situations; and anti-tank units have the potential to change the game on ground-heavy maps with their ability to bolster a defensive line.

The real game-changer, though, is the ability to level up units. As a unit kills enemies, its offensive and defensive power rise, up to three times. If you’re playing from a defensive or opportunistic stance, leveling up units doesn’t make much of a difference to the basic rock-paper-scissorsness of the gameplay: a leveled-up copter will still get wiped out by an anti-air unit, and leveled-up medium tanks are still fodder for rockets. If you’re trying to plan ahead a few moves, though, the difference between a new tank and a veteran can radically change your strategies. Rather than sending a flood of cheap units over the top against the enemy, it’s now often better to take a more deliberate approach, protecting units long enough to strengthen them and tip the scales in your favor. Where the cost of repairs seemed like a burden in previous games, it’s now a pretty wise investment if it results in a longer-lived, stronger tank.

Oddly, a strategy in which you nurture and level up your units instead of throwing them at the enemy willy-nilly leads to a greater emotional investment in those units. When you sacrifice a veteran-ranked cruiser to punch through an enemy line, or your toughest war tank gets isolated and surrounded by enemy units, your feelings of loss are real, if slight. So even if Advance Wars has severed the player’s relationship with its main characters, it has managed to strengthen his or her relationsip with the nameless, faceless sprites in the game itself. Call it the Companion Cube effect.