Points, name
7, half construct
3, abberation
3, deathless spirit
-1, negative energy affinity
2, climb speed 20
2, swim speed 20
0, small size
4, advanced stats, +4 dex, -2 str, +2 mental stats
3, SR 11+ lvl
1, stalker,
6, fast healing
4, DR 5/magic
Halfcontruct, deathless spirit and negative energy are due to them being made and in part with black blood.
Abberation is due to form. Climb and swim speeds also come from form, but of course were reasons for choosing such a form.
SR, DR, and fast healing were intentionally adding to compensate for the difficulty in healing. The advanced stats come from the care and attention in the making, essentially are the masterwork bonuses.
Stalker comes from the fact that hiding and seeing part of the purpose of the form.