Ultimate Program

The Ultimate Program is a very rare program that is found in only a select few NetNavis. A NetNavi that possesses this program has the potential to become the "Ultimate NetNavi" because the program allows a NetNavi to evolve and adapt to any situation on their own, without the need of a human to give them upgrades or modifications, resulting in very great power and unlimited potential. The program is supposed to be incorruptible, but if it does become corrupted, then it will absorb large quantities of bugs in order to repair itself.

The Ultimate Program was only seen in the Anime and not in the Video Games series.

Alive:

 * Bass.EXE
 * MegaMan.EXE
 * ProtoMan.EXE
 * Iris.EXE

Deceased:

 * PharaohMan.EXE
 * Grave Virus Beast

Uses
Each Navi that had the Ultimate Program had a unique ability displayed multiple times in the anime that allowed them to either win battles, become stronger, or have special unique attributes.
 * MegaMan.EXE:
 * The Ultimate Program enabled MegaMan to make use of the Style Change in the beginning, obtaining HeatGuts, WoodShield, ElecTeam, and AquaCustom Style. When the bug that was inside Bass entered MegaMan, his Ultimate Program invoked a Style Change in an attempt to repair itself, the Bug Style. His Program was powerful enough to overpower the Grave Virus Beast and ProtoMan's Ultimate Programs, absorbing the entire Net, before restoring everything after Lan got through to MegaMan.
 * After losing Style Change after having performed Cross Fusion with Lan, MegaMan obtained the Double Soul instead, taking other Navi's strengths and abilities into his own. Bass attempted to absorb MegaMan's Ultimate Program to become a super powerful being that could face Duo, but was thwarted with ProtoMan's intervention. When Bass had succeeded in absorbing MegaMan's Ultimate Program, he couldn't control it, with resulted in MegaMan activating the Double Soul instead and becoming Bass Cross.
 * It is likely that MegaMan's ability to merge with Trill to enter a Gregar and Falzar Beast Out was also a result of MegaMan's Ultimate Program. Later on, after MegaMan could access the Beast forms at will, he also obtained the ability to Cross other Navis as well and merge it with his Beast forms as well.


 * Bass.EXE:
 * When Bass was born from PharaohMan's remaining data, he lacked the Ultimate Program, as it was used to create the Grave Virus Beast. For that, Bass had an instinct to absorb data and bugs into himself, and eventually learned of his origins which led him to attempt to merge with the Grave Virus Beast, but he had been absorbed instead. After MegaMan had successfully restored the Net and deleted the Grave Virus Beast, Bass had obtained his Ultimate Program again, becoming whole once more.
 * Bass' Ultimate Program seems to be similar to his game version's Get Ability Program, as Bass attempted to absorb MegaMan and ProtoMan, though he failed to absorb either. He had absorbed MegaMan when MegaMan offered it to Bass to stop Nebula Gray, though Bass couldn't handle MegaMan's Ultimate Program and nearly self-destructed, forcing MegaMan to use Double Soul instead. After separating and being absorbed into an abyss, Bass managed to absorb the remaining power of Nebula Gray to become much more powerful that he could face Slur, who had easily defeated Bass before, and overpower the extraterrestrial Navi, eventually deleting Slur at the end.


 * Iris.EXE:
 * Iris' Ultimate Program wasn't used for battle, but it is likely that her Ultimate Program is what allowed her to enter the human world and the Net at will, as well as taming MegaMan's Beast Out states, and even helping a proper merge with Trill to enable MegaMan to control his Beast Out.


 * Grave Virus Beast:
 * It was created from PharaohMan's Ultimate Program, and it allowed the beast to grow stronger with every Navi and data that it could absorb. It allowed the beast to easily take on the most powerful of attacks and break through powerful firewalls that was used to contain it. It was only Bass and MegaMan Bug Style that could stand up to the beast, though Bass ended up being absorbed himself when he attempted to absorb the Grave Virus Beast. When it attempted to absorb MegaMan, it was ultimately absorbed and deleted, though Bass had reclaimed his Ultimate Program by then.


 * PharaohMan.EXE:
 * Though his Ultimate Program was used in the Grave Virus Beast and Bass, PharaohMan didn't display any unique abilities for battle, but instead was a very powerful Navi that could easily take over the Net by controlling the flow of data. Even an army of BomberMan.EXE and StoneMan.EXE could defeat him, and he easily destroyed the army. Despite how the power in SciLabs was shut down, PharaohMan successfully rebooted the entire system, despite how it shouldn't have been possible. It was only when MegaMan and ProtoMan had used a Double Program Advance on him that PharaohMan was wounded, which led to his capture, and eventually him self-destructing to prevent himself from being used by a human.