In this form, the user's appearance changes dramatically, gaining a massive increase in strength and muscle mass.
Usage and power
Roshi uses this state when he puts out the fires on Fire Mountain, to destroy the Moon during the 21st World Martial Arts Tournament, when fighting Frieza's soldiers and during the Tournament of Power.
In this state, Master Roshi is at his full power and can perform many of his techniques at their full potential, most notably his MAX Power Kamehameha. While its full power is unknown, Roshi was able to easily destroy the moon, while the likes of even King Piccolo could only destroy a city. During the original Dragon Ball, however, the form is deeply flawed; Roshi's movement speed is slowed to the extent that he barely moves when in the form and using an energy attack while in this form will waste almost all of his energy. In addition, if he had been crippled by either an illness or suffering from intoxication since at least two days earlier, attempts to use the form will result in the user being left addled and unable to focus before depowering due to residual effects, which is best demonstrated when Roshi, who had just recovered from a bad hangover from a Hanami picnic, attempted to use his Max Power form to fight Broly, only to end up backing out at the last minute due to residual alcohol intoxication being amplified in Broly - The Legendary Super Saiyan.
When Roshi uses the form once more in Dragon Ball Z: Resurrection ‘F’, he seems to have better control over it, being more mobile and being able to use more than one energy attack.
During the Tournament of Power in Dragon Ball Super, Roshi uses this against Dium from Team Universe 10. In this state, he was able to use his MAX Power Kamehameha to make Zium fall out of the stage. Later, he uses it against Ganos from Team Universe 4 and pushed himself beyond his limits, which was powerful enough to knock Ganos in his Avian form out of the ring. However, Roshi used up a lot of life force using the attack, leaving him in a near dead state until he was revived by Super Saiyan Blue Goku. Finally, he uses this state against Frost though finds himself far outmatched by an enemy who has to hold back so that he does not kill Roshi.
In Dragon Ball Super, during the preparation for the Tournament of Power, Roshi falls under the spell of Yurin, a jealous old friend of Tien. Under her witchcraft spell, Master Roshi no longer held back his power and fought with 100% power. At maximum power, he was able to quite easily overpower and would have killed Tien had Goku not saved him and briefly held his own against Goku's base form but was in the end quite easily beaten by Goku's Kamehameha after he put up no defense because he received no commands from Yurin. Goku said that Roshi has been doing a lot of training in secret and is quite shocked at what he is capable of when he is actually serious and not holding back.
Video Game Appearances
The form also appears in Dragon Ball Heroes, where it is referred to as Super Serious Turtle Hermit (亀仙人の超本気).