May has been a terrific month for fans of classic SEGA games. First Sonic the Hedgehog 4: Episode II launched last week on multiple systems.  Now four retro collections bearing the 'SEGA Vintage Collections' label are coming exclusively to Xbox Live Arcade over the next two weeks (sorry PS3 users). This Wednesday, the single-player Monster World Collection and Alex Kidd & Co. Collection debut at 800 Microsoft Points a piece. On May 30, they will be followed by Golden Axe Collection and Streets of Rage Collection for the same price.

This month's Co-Op International column takes aim at Espgaluda II Black Label. Not only is the title a mouthful, the game itself is full of bullets! Bullets and flying teenagers with psychic powers, oh yeah. Luckily for shoot-em-up fans, this one's not too tough to import.

We here at Co-Optimus have been anxious to play Sonic the Hedgehog 4: Episode II ever since we learned it would feature the return of Sonic 2-style co-op. The game is now live on Xbox Live Arcade, Playstation Network, and Steam, so teams of players can once again step into the shoes of Sonic and his effeminate pal Tails and take on the dastardly Eggman. To drive the point home, SEGA has released a short-but-sweet trailer showcasing many of Episode II's highlights (as well as the choice bonus content for Episode I owners).

In the closing days of World War II, one sniper (or a pair of snipers) must sneak behind enemy lines to liberate a group of rocket scientists. Pair up with a friend in four different online co-op modes and take aim at hordes of nasty Nazis in Rebellion's finest game yet.

These days, just about every digital software platform under the sun offers giftcards at retail: Xbox Live, Playstation Network, and iTunes, for example. One major content provider has always lacked a retail presence though: Steam. Sure, Steam offers the ability to gift or trade individual games, but that's more of a specific gift rather than a general one. Plus it required the use of a credit card or PayPal account; you can't make cash transactions online, silly head.

Japanese developer CAVE's latest shoot-em-up Akai Katana hits stores this Tuesday, May 15 courtesy of Rising Star Games' newly-opened US branch. Bullet hell shmups like Akai Katana are notoroiously difficult, filling the screen with hundreds of enemy bullets at once. Rising Star knows this and has considerately created an orientation trailer, explaining just how the gameplay works. It won't make your reflexes any faster, but at least you'll know how to use the ship's various attacks and Phantom mode transformation before you play.

Ghost Recon: Future Soldier is only a few weeks away, so it might be time to clear out your backlog of Ghost Recon and other Tom Clancy games. At least, that's what Microsoft thinks, hence the Tom Clancy DLC sale on Xbox Live. Downloadable content for both GRAWs, Splinter Cell Conviction (my favorite Clancy game), and even the high-flying HAWX games are all on sale for half off for Xbox Live Gold members until Tuesday.

What hath science wrought? Fable Heroes grafts the familiar Fable world onto a beat-em-up/party game with predictably mixed results. Its only hope for redemption: drop-in, drop-out combo co-op!

Orion: Dino Beatdown, the co-op-centric first-person dinosaur shooter, debuts on Steam in just a few more days. To help train the next generation of dinosaur hunters, indie developer Spiral Game Studios has released one last video documentary to tease the game before its release. Give it a watch (or simply read on) to find out about the game's worlds and the repitllian beasties that will inhabit them.

Attention dinosaur lovers/haters. Co-Optimus is following up last week's World Gone Sour contest with a brand new giveaway. This time we're shelling out five copies of the very promising first-person shooter Orion: Dino Beatdown from Spiral Game Studios. Orion launches on Steam this Friday, May 4th and supports 5-player online co-op. We'll have a full co-op review very soon. In the mean time, why not try to win it for free?

Tom Clancy's Ghost Recon series returns after a long absence this May as Ghost Recon Future Soldier. Ubisoft has taken advantage of the copious development time since GRAW 2 by adding lots of fresh ideas such as the new Gunsmith feature. They've even created a humorous trailer just for Gunsmith, which at turns had me either smiling or cringing, but did nothing to lessen my excitement for the game.

Last month we reported on a rumor that the Golden Axe and Streets of Rage series would be getting new Xbox Live Arcade releases. Those rumors have been all but officially confirmed by Xbox.com product pages for both collections, which showed up and then vanished yesterday. Thankfully a NeoGAF user captured the product descriptions and screenshots for both releases, which are titled SEGA Vintage Collection: Golden Axe and SEGA Vintage Collection: Streets of Rage.

Co-Optimus has been covering Arcen Games' PC and Mac title A Valley Without Wind in pre-release form for over a year. At long last, A Valley Without Wind is available on Steam, the platform of choice for many computer gamers. What's more, through May 1 you can get it for $13.49 - ten percent off the regular price of $14.99. It's also available on GamersGate and Impulse.

Steel Battalion: Heavy Armor, the Kinect-exclusive followup to Capcom's classic mech simulator, won't be released until June. But gamers now have some incentive to order it straight away, thanks to three retailer-specific preorder bonuses. Amazon, Best Buy, and GameStop are all offering unique armor sets with which to deck out your mechs. Capcom has even gone the extra mile to aid players in their purchasing decisions, creating trailers for each armor and explaining their functions.

Details are still scarce about Ska Studios' upcoming Xbox Live Arcade exclusive, Charlie Murder. We know it's a four player beat-em-up with RPG elements, which creator James Silva has coined as a brawl-PG. I'm fond of RPG-eat-em-up, myself. Anyway, the game revolves around the members of a band called Charlie Murder setting out to stop the evil band Gore Quaffer and its monstrous minions from doing bad things. That's still a bit vague, but three new screenshots (plus a brief video from PAX East) give us a better idea of what to expect.