[quote=Dead Cruiser]
To be fair, you never actually said what a "blood pact" was. My thought with this one was that the spirit was sort of the child's guardian, having been bonded to it since the character's infancy and essentially raised it. Thus leaving the conditions of the pact's formation a mystery to be explored later.
[/quote]

Sorry for the confusion.. "Blood Pact" literally means a Pact signed for in blood/life force, of either yours, or another's, and typically in great amounts. - and you still need the power/ability to control it. And as for the Spirit being a sort of 'Guardian', thats essentially what my character's spirit was for him, you're probably better off in that case with a Humanoid Spirit, they're typically more intelligent and can speak languages. I do like the idea of a mysterious pact, but again, I would suggest a Humanoid Spirit.

[quote=Terminal]
Or somebody murdered their family to bind the gargantuan to the child - I imagine controlling a summon by proxy has certain advantages and disadvantages.
[/quote]

That is totally possible, though it'd probably be much easier to murder a family and bind the spirit to yourself. Gargantuans probably won't care about the source of blood, as long as they get a lot of it. I mean, Rtron's character just murdered 8 of his teammates and used their blood to bind his Gargantuan. 

Gargantuans are essentially this world's version of Demi-Gods. They are going to be extremely powerful, and quite far and few between. Rtron has one for Co-Gm/plot/emergency reasons, the most powerful of spirits I would like most characters to be able to control are high-tier Humanoids Also, the only Spirits available for play are Humanoids, because they have intelligence similar to/greater than that of humans.