JUST SO YOU KNOW...
I'll be covering pretty everything Geo has. It's never stated that Geo lost the power of the Star Force after the first game (And in fact, it's likely he at least kept some of it, hence why Elemental Cyclone and Atomic Blazer return in the third game), and it is OUTRIGHT STATED in the second that Mega Man kept the power of the OOParts even after it had been removed from Omega-Xis. This is why Geo can still use Thunderbolt Blade in the third game, complete with Thunder Zerker's sword. However, I will not be covering all the Noise forms (Only the Finalized forms) or Double Tribe forms. Also, as it should go without saying, not ALL Battle Cards would be used (Considering there are over... what, 100 different types? That'd take far too long!). With that out of the way, let's begin!
PERSONALITY AND BACKSTORY
A long time ago, there was a planet called Planet AM. On this planet lived the AMians, aliens with bodies made of electromagnetic waves. However, on one fateful day, Planet AM was destroyed by the planet-busting weapon Andromeda, on the orders of Cepheus, the king of the neighbouring planet, Planet FM, due to the king's paranoia. Only a few AMians survived the destruction of their home-world, one of whom was an alien called Omega-Xis, who fled to Planet FM to live, albeit in disguise. However, on another fateful day, the FMians attacked a space satellite belonging to the humans of planet earth. There, Omega-Xis had a chance encounter with a man named Kelvin Stelar. After stealing the Andromeda Key from Planet FM's forces and turning the crew of the Satellite into EM bodies in an attempt to save them, Omega-Xis fled to Earth in hopes of stopping Andromeda from being used. There, he ended up meeting Kelvin Stelar's son, Geo. Geo, having been told that his dad disappeared three years prior to this meeting, was depressed and a bit of a loner. He dropped out of school and was self-taught, but often went to Vista Point to stargaze (And this is where he met Omega-Xis). The two then worked together to stop a train that had been infected with Wave Viruses, and it was here where they first performed an EM Wave Change. Geo would later come up with the alias Mega Man when questioned by Luna Platz, who was trying to coax him to come to school. (Although she did not become aware of Geo's identity until much later). From there, they proceeded to fight off the FMian's invasion and then save the world two more times. Once from the ancient civilization of Mu, and the other from the gigantic Meteor G, which would have crashed into the planet.
Geo is generally a friendly person, and in many ways his personality is somewhat similar to that of the unsung heroes who worked to save the world two hundred years prior, Lan Hikari and MegaMan.EXE. He is highly interested in astronomy, and is afraid of ghosts.
Omega-Xis on the other hand is brash, headstrong and loud-mouthed. He's quick to pick fights and very prideful.
ABILITIES AND EQUIPMENT
Geo, being an ordinary human boy, has no real abilities... at first. He does have the pair of goggles known as the Visualiser, though. This allows him to see EM waves, albeit at the cost of obscuring his vision of the real world.
Omega-Xis, as an AMian, has the unique ability to turn living beings into wave bodies. This is how he saves the lives of the crew of the Space Satellite Peace (including Geo's dad Kelvin).
However, the primary ability that Geo and Omega-Xis rely on to solve most of their problems is the EM Wave Change. With this ability, a human and EM being fuse together to become a Wave Being, combining the properties of both the EM being and Human. In this form, Geo and Omega-Xis go by the Alias... you guessed it- Mega Man. Geo is typically the dominant personality when fused as Mega Man (a stark contrast to most of the other EM Wave Changes that have been performed in the series.), and in this state Geo possesses incredible speed, strength and durability. One of the unique abilities Geo demonstrates in the anime is the ability to alter his physical properties to act more like an EM wave or more like a physical object. Despite this, Geo is in fact completely made of EM waves while in the form of Mega Man. This, naturally, affords Geo the ability to move at the speed of light. Geo is also exceedingly versatile, due to his ability to use Battle Cards. There have been a large number of battle cards that Geo has used, but to keep things simple, we'll be sticking to the ones that are the most Iconic. Also, no cards that call in other EM beings. So on that note, we'll start with Break Saber, Geo's most-used battle card. This battle card turns Geo's arm into a powerful blade capable of breaking through the enemy's defenses. This does have limits (Like when, in the anime, Geo was unable to pierce through Andromeda's armor with it), but it also hits very hard. Geo also extensively uses the Gatling Gun/Mad Vulcan type Battle Cards, which turn his arm into a, well, Gatling gun for a rapid-fire assault. He also notably uses Paralyze Knuckle, a punching attack which stuns the opponent, allowing for an easy follow-up, Freeze Knuckle, which is like Paralyze Knuckle, only it freezes the target solid instead, Plasma Gun, a ranged paralyzing battle card, Jet Attack, a charging attack, and Barrier, which protects him from attacks. Failing this, Geo can naturally pull up a shield to block attacks and fight using his own version of the Mega Buster, which passively charges when not in use and can be rapidly fired. He can also lock onto foes and strike using the Mega Attack.
...And now we get onto the transformations. Geo has a LOT of these, so we'll be going over them by game. Firstly, we have...
STAR BREAK
Partway through the first game, Geo gets gifted the powers of one of the three Great Sages of Planet AM (or all three in the anime), and is able to transform into a more powerful form resembling the respective Satellite. Each of the three Star Break forms has different properties, and a separate Star Force Big Bang, a super move unique to that particular Star Break Form.
Fire Leo, naturally, has an affinity of fire. His Charge Shot in this form releases a stream of flames, and Geo's Star Force Big Bang in this form has him channel his inner Goku with Atomic Blazer, releasing a devastating stream of flames towards anybody unfortunate enough to be fighting him. In this form Geo is also capable of shrugging off attacks. He still takes damage but does not flinch from them, allowing for uninterrupted assaults. However, if Geo is hit by an Aqua-based attack, he will take double damage and be forced out of the Fire Leo form.
Ice Pegasus has an Aqua affinity and grants Geo Float Shoes which allows him to ignore the negative effects of terrain. He recovers on Ice while in this form and shoots out a blade of ice for his Charge Shot, and his Star Force Big Bang in this form, Magician's Freeze, causes a massive cluster of Ice to burst from the ground, freezing anything hit solid in an instant. However, should Geo be hit by an Electric-based attack, he will take double damage and, you guessed it, be forced out of the Ice Pegasus form.
Green Dragon has a Wood affinity and grants Geo immunity to status ailments such as paralysis. He recovers on grassy panels and fires a barrage of leaves from his buster for his charge shot. His Star Force Big Bang is Elemental Cyclone, in which he encases himself within a tornado of leaves and strikes the foe in front of him. However, should Geo be hit by a Fire-based attack in this state, he'll take double damage and be forced out of the Green Dragon form.
Next...
TRIBE ON
When Omega-Xis accidentally consumed the OOParts in Mega Man Star Force 2, Geo was granted the ability to enter a special form based on the OOPart he's currently using. These forms are similar to the Star Break Forms: They each have an Elemental Affinity, a unique charge shot, weaknesses that force the user out of the form, and a unique Super Move. In this case, a Link Force Big Bang.
The Sword of Zerker transforms Geo into the Thunder Zerker Form. In this form, Geo has an Elec Affinity and can strike the ground with a paralyzing shockwave from his blade via his charge shot.. He can also charge non-screen dimming chips for use in a large combo without flinching. His Link Force Big Bang is Thunderbolt Blade, with which Geo uses the Sword of Zerker for a powerful three hit combo. Thunder Zerker's weakness is Wood Element.
The Star of Ninja transforms Geo into the Wood Shinobi Form. In this form, Geo has a wood affinity and can launch intangibility-piercing Ninja stars with his charge shot. He can create a body-double to counter enemy attacks. His Link Force Big Bang is Demon Flurry (Fuuma Shippujin) which barrages the enemy with a large number of Shuriken. Wood Shinobi's weakness is Fire Element.
The Rock of Saurian turns Geo into the Fire Dinosaur Form. In this form, Geo has a fire affinity and launches an explosive blast which hits everything behind the target with his charge shot. He has the same Super Armor that the Fire Leo form does (He doesn't flinch from attacks), can charge non-dimming cards for an attack boost, and his Link Force Big Bang is Genocide Blazer, with which he strafes the entire field with a turning Atomic Blazer.
However, Geo has a fourth Tribe Form, entered by combining the power of all three other Tribe Forms: Tribe King. This combines all three of the Tribe Forms' passive abilities, has NO elemental weaknesses and has a unique charge shot that unleashes three elemental waves from the sword, each representing one of the three OOParts. On top of this, it has its own unique Link Force Big Bang: Kaiser Delta Breaker, which unleashes a massive wave of energy that strikes the targets with the power of all three OOParts. The only problem is, Tribe King has a time limit and, once the time is up, Geo will be returned to his base form.
Lastly, we've got...
NOISE CHANGE
When Geo receives the Ace/Joker Program in Star Force 3, he gains the ability to absorb large amounts of Noise into his body to take on one of two incredibly powerful forms depending on the program.
Both of Geo's Finalized Noise Forms share a few common features. They each hold heavily empowered battle card folders including all five Vibrant Noise Forms' Noise Force Big Bangs (Meteorite Barrage, Atomic Blazer, Elemental Cyclone, Thunderbolt Blade, Dynamic Wave) and their own unique Noise Force Big Bangs, the Mega Buster's power is maximized, they have no elemental weaknesses and do double damage when locked on. There are only two problems. The first is that, just like with Tribe King, there is a time limit for how long Geo can stay finalized for. The second is that, while Finalized, Geo completely loses the ability to use Charge Shots.
Red Joker focuses on delivering powerful armor-piercing blows. having the Super Armor mentioned before in Fire Leo, Fire Dinosaur and Tribe King, and also having Green Dragon's Status immunity. However, what is unique to Red Joker is the Noise Force Big Bang Red Gaia Eraser, which unleashes a powerful laser barrage on the surrounding area, ending with a massive explosion.
Black Ace relies more on delivering quicker blows and preventing the foe from escaping via usage of intangibility. It has Float Shoes, much like Ice Pegasus, and Air Shoes, which allows him to walk over holes, and, unlike any other form of Geo's, automatically locks onto enemies. His Noise Force Big Bang is Black End Galaxy, which traps enemies in a Black Hole before slicing through it, causing the black hole to explode. This completely ignores intangibility.
FEATS AND WEAKNESSES
Geo's feats are extremely impressive. He's taken down the likes of Andromeda, a planet-busting superweapon, Sirius, a being who can create black holes to easily consume planets (and has been implied to do so many times prior to targetting Planet FM) and, when Clockman went back in time to mess with the timeline and Geo followed, he ended up getting into a fight with his predecessor, Megaman.EXE. While Geo DID, in fact, lose, he DID put up a good fight. It is also highly likely that Geo was holding back, so as to avoid deleting Megaman.EXE (Which would, naturally, mess up the timeline, something which Geo was trying to PREVENT from happening).
Despite all these incredible feats of consistently taking down planet-busters and likely being the strongest Mega Man to date (You could make arguments for X being stronger? But then again, Geo's much faster...), He is not perfect. Sustaining too much damage will forcibly end the EM Wave Change and separate Mega Man back into the seperate forms Geo and Omega-Xis, which will render them completely helpless. This can also happen if too large a rift form between Geo and Omega-Xis, as the EM Wave Change is reliant on the two working in unison. In fact, this actually happened in the Star Force Anime where, when Gemini Spark accused Omega-Xis of killing Geo's father, Geo lost trust in Omega-Xis and the Wave Change ended right there. Geo's transformations either have a distinct weakness that can be abused (Like the elemental weaknesses of his Tribe [Except Tribe King] and Star Break forms), or run on a time limit (Like Tribe King and the Finalized Noise Forms).
Don't let that fool you, though. Geo is incredibly powerful, and well deserving of the 'Mega Man' title. He's saved the world on three separate occasions, two of which having the power to destroy the whole planet (And the third was still at least a continent-buster, given how the end of that whole mess was somebody trying to drop a flying continent).
OVERVIEW
+Extremely fast. Lightspeed at bare minimum due to being composed of EM waves.
+Easily a planet-buster, given an abundance of feats.
+Exceedingly versatile due to the various transformations and Battle Cards available to him.
-Star Break and Tribe On forms have elemental weaknesses.
-Black Ace, Red Joker and Tribe King have time limits.
-Sustaining enough damage in any state will forcibly end the EM Wave Change, rendering Geo and Omega-Xis helpless. This will also happen if Geo and Omega-Xis end up disagreeing too much.
