Late last year, when I was playing Valve's brilliant puzzle game "Portal," I felt a weird sensation: Laughter.

I'm not sure when I first noticed it; perhaps it was when GLaDOS, the insane artificial intelligence that was tormenting me, promised "grief counseling and cake" after my ordeal. What really threw me was the idea that a video game could make me laugh out loud.

So few games even try to be funny that it's refreshing when something like "Grand Theft Auto IV" crams in so much comedy, mostly through its broad TV, radio and Internet parodies. Nintendo's Mario games, particular the "Paper Mario" adventures, can usually be counted on for a few laughs. And Sony's Ratchet and Clank have become the medium's most reliable comedy team.

But most video games take themselves way too seriously. Would it kill the hard-boiled heroes of "Halo" or "Gears of War" to crack a smile very now and then? Once you've saved the world (again) in "Call of Duty," don't you deserve a little comic relief?

"Penny Arcade Adventures: On the Rain-Slick Precipice of Darkness, Episode One" (Hothead, for the Xbox 360, $20): Jerry Holkins and Mike Krahulik have been producing the Penny Arcade Web comic, an acerbic take on the video-game industry, for nearly a decade. "Penny Arcade Adventures" is a gutsy attempt to bring their sensibility to an actual game, and it's a real delight.

As the game begins, your character's house is destroyed by a giant robot. With the help of Tycho and Gabe - Holkins and Krahulik's alter egos - you have to find out what's behind the robot attack. Is it the vicious mimes? The demonic clowns? The stinky hobos? The jokes are wonderfully depraved (the clowns, for example, make squeaking noises as they die) and, for the most part, too raunchy for kids.

The laughs are complemented by the strip's distinctive art style, which makes this one of the best-looking games on Xbox Live Arcade. And the fighting mechanism is really clever, using a turn-based system that will feel familiar to role-playing gamers. The big drawback of "Episode One" is that it only takes about five hours to play. I hope we don't have to wait long for the next chapter.

Three stars out of four.

"Teenage Zombies: Invasion of the Alien Brain Thingys" (Ignition, for the Nintendo DS, $19.99): This goofy adventure deftly combines two B-movie threats - the alien invasion and the undead uprising - in a way that hasn't been seen since Ed Wood's "Plan 9 from Outer Space." What if Earth were attacked by disembodied, floating brains? Who better to stop them than zombies, who, after all, feast on gray matter?

The three zombies who emerge from their graves are Lefty, who has one stretchy arm that lets her reach high spaces; Fins, whose tentacles enable him to climb walls; and Half-Pipe, a legless skateboarder who can squeeze through tight spaces. You have to keep switching between the characters to hunt down all the brains, making use of power-ups like Fins' flaming vomit and Half-Pipe's hoverboard.

There are also some wacky minigames, like a corpse-assembly challenge, and witty narration that captures the comic-book vibe. (In a smart touch, you can jump on top of the dialogue boxes.) But the fundamental gameplay gets repetitious after about an hour, and "Teenage Zombies" runs out of charm well before the final battle with the Big Brain.

Two-and-a-half stars.

"Battle of the Bands" (THQ, for the Wii, $49.99): This rhythm game adds an element of sublime silliness to the dueling-instruments competition popularized by "Guitar Hero." The gimmick is that you don't have to be a rocker - you can control a hip-hop posse, a country combo, a mariachi group or even a marching band.

It's very funny to hear country twangers and mariachis dueling with their respective versions of, say, Cypress Hill's "Insane in the Brain." The 30 songs in "Battle" have all been remade in all five styles, so it'll take awhile to play through all the combinations. The gag wears thin in solo mode, but it's a hoot at parties.

The controls are much less sophisticated (and less expensive) than the "Guitar Hero" instruments. The end result isn't as challenging as the more popular guitar games, but it offers a nice change of pace.

Two stars.

On the Net

"Penny Arcade Adventures": http://www.rainslick.com/

"Teenage Zombies": http://www.teenagezombiesgame.com/

"Battle of the Bands": http://www.battleofthebandsgame.com/