Talk:Mashu Kyrielight/@comment-30319914-20170517080031/@comment-182.30.68.35-20170527043319

As far as I can tell, a "Possession Union" that creates a "Demi-Servant" is when a Heroic Spirit essentially merges into a human's body, granting the human the effective powers and 'identity' of the Heroic Spirit, as well as quite possibly a few bodily memories. Mashu is fully herself; she simply inherited Galahad's powers at the latter's consent. She also doesn't fully know how to shot web, at least at start. Galahad's own whereabouts is unknown; he's never showed up, that's for sure.

The process that creates a "Pseudo-Servant", on the other hand, such as El-Melloi II as Zhuge Liang or Tohsaka Rin as Ishtar, is caused when the Saint Graph of the Heroic Spirit in question is too abnormal to be normal summoned, and 'sleeved' into the vessel of a compatible human/person to enable a special summon.

The results differ - El-Melloi II inherited pretty much all of Zhuge Liang's powers and is capable of using them as himself because Zhuge Liang basically went "eh, I'll just give ya these, you go pilot and I'll hang back" or something like that. IIRC there was a text blurb where El-Melloi II mentioned "meeting" Zhuge Liang in a sense, and found his trains of thought to be utterly alien and inhuman, so his decision to let Waver pilot is probably for the best.

Ishtar is almost entirely Ishtar; in a story chapter she stated that because Divine Spirits have stronger 'selves' than humans, the Divine Spirit will almost certainly be dominant, but there's still shades of the vessel 'bleeding off' into the resultant personality - Rinshtar said that she's around 80% Ishtar, 20% Rin. Caster!Gilgamesh noted that she's a bit more well-adjusted because of this. That said, Ishtar and Rin are apparently nearly identical in terms of personality in the first place, so their compatibility is as good as it can be.

As an aside, Jaguarman has Jaguarman's stats and sets of values, but her personality is basically 99.99% Taiga. She does not like if someone brings that up, apparently.