"Ratchet & Clank: Full-Frontal Assault" is more than a minigame, but not much. Call it a little game.

But as Alan Jackson once sang, "It's all right to be little bitty." In fact, this is the most exciting "Ratchet & Clank" game in years. With this lombax-and-robot team, the usual drill is running around shooting tons of bad guys in bloodless fights involving zany guns, like one that turns enemies into sheep. "Full-Frontal Assault" incorporates the duo's usual button-mashing antics into a larger framework: the tower-defense genre, in which the object of the game is to protect a building from waves of enemies.

'Ratchet & Clank: Full-Frontal Assault'
» System: PS3, Vita
» Price: $19.99
» Rating: 3 out of 5 stars

Most tower-defense games cast the player as a disembodied god deciding where to place turrets around the enemy's target, but "Full-Frontal Assault" places you on the actual battlefield. Before long, you develop a nice rhythm, running around your base laying mines and building turrets between enemy waves, and then blasting bad guys when they show up.

"Full-Frontal Assault" isn't just a good tower-defense game; it may point to a new category of game, a happy medium between cheap mobile diversions and lengthy home-system adventures that lay siege to your life. It also may point to a new way of marketing games: Take a good basic concept, slap a couple of familiar mascots on the box and charge $20.

Clocking in at about five hours, not to mention cooperative modes over the Internet, "Full-Frontal Assault" quits while it's ahead. This little game is well worth the money (unlike some mainline "Ratchet & Clank" games that sell for three times the price), but it would be a more special experience if it didn't steal so many of its ideas from "Iron Brigade." That game was one of the best of 2011 -- and will set you back even less than this one.