[Yep, we're still going with big sister site Gamasutra's year-end retrospective, and this time, our own Eric Caoili looks back on 2008's best handheld games across all portable platforms -- from The World Ends With You to Patapon -- along with ten notable handheld titles that get honorable mentions.]

Throughout December, Gamasutra will be presenting a year-end retrospective, discussing notable games, events, developers, and industry figures of 2008, from the perspective of our position covering the art, science, and business of games.

Previously: 2008's top disappointments, downloadable titles, overlooked games, gameplay mechanics, indie games, surprises, PC games, and trends.

Next, we'll look at this year's top five handheld games and ten honorable mentions, the portable titles that managed to overcome their small-screen limitations to steal a big chunk of our time. The games picked are the editor's choice, and are chosen from the handheld titles released in North America during 2008's calendar year to date.

Here are our choices:

5. The World Ends With You (Square Enix/Jupiter, DS)

On a system that seems to receive a new forgettable Japanese RPG every other week, it's invigorating to see an original title like The World Ends With You, a game unique not only in its modern Shibuya (Tokyo district) setting and character designs, but in its story, which serves as a commentary on Japanese youth and hikikomori.

And it's from Square Enix, no less -- a studio recognized by most for its reliance on rehashes and spin-offs of established franchises, not for its catalog of peculiar and risky titles, which is an apt description for TWEWY. And while it's a surprise to see such an oddball title from the Final Fantasy publisher, it's even more astonishing that the company brought such an overtly Japanese game stateside.

TWEWY's bizarre combat system alone demonstrates how much effort the studios must have put into the game to make everything work -- players have to manage battles on two screens with two different input methods, also yelling into the oft-maligned microphone for some attacks. This shouldn't be fun at all, but somehow, it's one of the most enjoyable experiences on the Nintendo DS.

4. Aurora Feint (Danielle Cassley/Jason Citron, iPhone)

The most common reaction you'll see from players who've downloaded and played Aurora Feint -- besides mistaken accusations of the game acting as spyware -- is their surprise that this downloadable title is available for free.

Created in ten weeks by only two programmers, this addictive hybrid of RPG elements and Panel de Pon/Bejeweled-styled puzzles is more than just an iPhone clone of Infinite Interactive's Puzzle Quest; Aurora Feint's emphasis is on crafting instead of battling fantasy monsters. The game also adds an interesting twist to the formula by using the iPhone's accelerometer to tilt the board and puzzle pieces, as well as the system's multi-touch capabilities for pulling in additional puzzle blocks.

The game's more ambitious but less free follow-up, Aurora Feint II: The Arena, released just a month ago, adds new classes, leaderboards, and "asynchronous" player vs. player dueling. Gamers who prefer the original, however, can look forward to an inexpensive upcoming update adding chat and social networking features.

3. Mystery Dungeon: Shiren the Wanderer (Chunsoft, DS)

Considered by many in the know to be the finest Eastern-developed roguelike, Shiren the Wanderer finally made its way to the States after enjoying 13 years and now eight releases in Japan. This is probably one of the most hardcore and niche titles on any platform -- certainly a lot less accessible and yielding than its Pokémon Mystery Dungeon counterparts -- but someone had to give Shiren its due (and properly thank Sega for bringing over this game that hardly anyone bought)!

Though insanely difficult, punishing heedless adventurers at every turn and sending them back to the beginning town without any of their equipment or XP, Shiren is also immensely rewarding to those who can survive the game's trap-filled dungeons and monster-choked corridors. You'll need the resourcefulness of MacGyver, the preparation of Batman, and the prescience of Ender Wiggin just to make your way to the main dungeon's final boss, but you'll also feel as accomplished as all three of those fictional heroes when you finally get there.

2. Patapon (Pyramid/Japan Studios, PSP)

Part RPG, part real-time strategy game, and part rhythm game, Patapon is absolutely adorable, from its chanting, peppy eponymous tribe, to their catchy "pata-pata-pata-pon"s sung as they march towards enemies and intimidatingly large bosses.

Despite its jaunty characters and inviting, silhouetted environments, the game can be exceedingly difficult, demanding that players time their button presses perfectly to the beat for several minutes at a time, and that they watch out for subtle visual cues from enemies and their tribe to decide whether to retreat, defend, or attack.

Like Shiren, though, mastering the art of commanding your troops with simple drumbeats, and then successfully leading them against their mighty foes brings a cheerful sense of reward that will have players tapping their foot along with their tribe's steps.

1. Space Invaders Extreme (Taito/Gulti, DS/PSP)

It was a big year for Space Invaders; celebrating its 30th anniversary, the franchise went extreme, got even, and made plans to further mutate with an Infinity Gene.

As with Namco Bandai's 2007 re-vamp Pac-Man CE, Space Invaders Extreme retains all the fun and challenge of the original arcade game, but modernizes it with a stirring techno soundtrack, clever boss fights, an interesting power-up/level-up system, new enemy types, and branching stages.

While the game is excellent on both the PSP and Nintendo DS, we prefer the latter version for its online multiplayer and leaderboards, support of the import-only paddle controller, more pleasing soundtrack, Mr. Esc (from Exit) cameos, and single-cart multiplayer. An Xbox Live Arcade release is also planned for next year with four-player co-op in the arcade mode and with background visualizers created by Llamasoft's Jeff Minter (Space Giraffe).

Finally, honorable mentions for some of our favorite handheld games in 2008 that didn't quite reach the top five go to: Soul Bubbles, God of War: Chains of Olympus, Chrono Trigger, Castlevania: Order of Ecclesia, Professor Layton and the Curious Village, Trism, Lock's Quest, Crisis Core: Final Fantasy VII, Princess Debut, and Bangai-O Spirits.

[Do you agree or disagree with these picks? Feel free to comment below. We'll pick the best reader comments on each list for our final retrospective, to debut on Gamasutra close to the holidays.]