gacha

Galahad isn’t a (True) Alter. He has no idea why he’s been summoned as an Alter and is noted to be a ‘Heroic Spirit bathed in fantasy’ and hints that he didn’t even exist. Anubis confirms it later where he says Galahad Alter is an existence solely dependant on the true Galahad’s fame and prestige.

More information. Anubis goes on to talk about how the Requiem Grail can’t outright control what it summons, but it can change it. It recognised Galahad as a threat to its control and fucked his shit up. Otherwise Anubis notes that Alter’s power is nowhere near the original and that the actual Galahad’s Noble Phantasmal would be beyond anything summoned in the world of requiem. And that even his authority would have no chance before them.

They touch on Longinus as well. Longinus isn’t anything special as far as Servants go, it’s only due to the HUGE difference in True Servant containers and the Requiem grails containers that he’s so strong. His NP is apparently the only thing that stands out.

Galahad’s Noble Phantasm talk hints at God being heavily involved with certain Servants NPs, it isn’t clear on what it is exactly. But it seems to imply that Galahad’s Noble Phantasms are related to Gods Authority.