Sterling Vermin present the Pactborn - Tieflings as a subrace of Warlock kin!

[Gr7mm Bobb]

While the template is solid for the most part and flavor is cool I can't help but think that it is a little too specific for a race, especially with all these sub-races. Aside from that I think you might have a couple of errors.
1. Lesser Restoration is a 2nd level spell and Daylight is 3rd level spell, now while you could argue that the overall usefulness of such abilities in regards to actions put them about equal maybe you should then cut one of the resistances of the Aasimar.

The Tiefling and Aasmir are replicated in these docs as they are in the PHB and DMG respectively. Asmirs were listed with 2 resistances, idk, but wizards called it balanced.

2. The Methuselah though seems to be the weakest one only getting Inscrutable Madness Insight. While definitely cool it is 1 roll and the roll may not be all that beneficial if you get somewhere in the middle. I would think psychic resistance would fit in nicely or perhaps just darkvision if you don't want it to overlap with other features.

I do agree here that maybe the Methuselah should maybe have darkvision, or maybe even detect thoughts as a legacy spell.

Overall I do love the way all of these have been presented.

If it's alright by Sterlingvermin, I'd like to draw up a subrace for their Cosmic Machine Patron.