Take on the world's toughest NetBattlers and save the planet from an asteroid while you're at it in Mega Man Battle Network 4: Red Sun or Blue Moon. Lan, a school kid, does the walking while his computer program, Mega Man.exe, does the virus stompin'.

The Web is buzzing with news of the big Den Battle Tournament. It's the ultimate battle between Navis (electronic personifications on the Net). Lan and his Navi, Mega Man, must find a way to get into that tournament.

When you control Lan, he skates around the city and chats with his fellow citizens. Some give him clues for completing his mission. If you're ever unsure what Lan is supposed to be doing, press the L Button and Mega Man will remind you of your task or give you a hint on how to finish your task.

When Lan needs to go on the Net to complete his mission, he jacks in his PET (PErsonal Terminal, which holds his Navi) and Mega Man logs into action. The Net can be a scary place. Although it buzzes with key info, it's also littered with viruses that Mega Man needs to delete.

NetBattle

Once Mega Man crosses the path of a virus, he enters the battle arena. On the left side of the screen, Mega Man has a nine-square block in which to move around. The viruses have a similar block on the right side. When the battle starts, Mega Man can access six chips chosen randomly from a battle folder of 30 chips.

Once Mega Man has his chips, the battle begins. Mega Man can use his battle chips by pressing A. He can use each chip only once before he has to reload. He's allowed to reload once every 15 seconds. Once you're cleared to reload, press the L or R Button. The battle pauses and a screen appears, showing you six more chips you can choose from. Once you make your choice, the battle resumes right where it left off. Mega Man can also fire his Mega-Buster by pressing the B Button. This process continues until Mega Man defeats the viruses or loses all his hit points.

You usually win chips after you defeat viruses. You can mix and match these to upgrade Mega Man's performance. Mega Man can have up to four copies of one type of chip in his battle folder. The more copies of a chip you have, the more likely one is to come up for you during battle.

Tournament

Both Red Sun and Blue Moon share the same storyline until you get to the big tournament. Here, each game has a unique set of six opponents, one of which will randomly be assigned to battle you. Eight players, including yourself, participate in the tournament. Defeat your opponent's Navis in NetBattles to advance to the semifinals and finals.

Before Lan faces his opponent in the tournament, however, he must complete a story- mode mission. Just before battling his next tournament rival, something terrible happens. Being the great kid he is, Lan leaves the stadium to go right the wrong. As it turns out, the tournament is just a test to find the best NetBattler and recruit him to help save the planet from being smashed by an asteroid.

Soul Mates

In a new twist, Battle Network 4 features Dark Soul and Soul Unison systems. Once you defeat an opponent in the tournament, you can use his Navi's special abilities for the rest of the game. Whenever Mega Man battles viruses or other enemies, you can sacrifice certain chips to fuse for a short time, a defeated opponent's attributes with Mega Man.

However, some dark, mysterious chips eat away at Mega Man's soul. They're also the most powerful. When Mega Man performs a Soul Unison with these dark chips, Mega Man becomes nearly unbeatable. However, every time he performs a Soul Unison with the dark chips, the dark powers eat away at his hit points, one point at a time. One point per use might not seem like much of a punishment, but Mega Man can never get those hit points back. As the game progresses, Mega Man starts performing unpredictably if he's been corrupted by the dark powers. Don't overuse the dark powers, as tempting as it might be.

Once you've won a couple of tournament battles, you can link up to another Game Boy Advance using the Game Boy Advance Link Cable. If a friend has either Red Sun or Blue Moon, you can battle him or her or trade collected chips.

Unique blend of action and RPG elements

Win chips to dramatically upgrade Mega Man's fighting skills

Two-player chip-trading and vs. modes with Red Sun or sister game Mega Man Battle Network 4: Blue Moon Game Paks

Debut of Soul Unison and Dark Soul systems