Sooo... yep, I do follow SU too.
I made my original gem as a peculiar cross between a cracked and a corrupted gem:
Amber was nothing but a nerdy explorer who got caught in the war against the Crystal Gems for planet Earth.
Not even capable of summoning her own weapon and havind the power of absorbing and channeling electricity (not exactly common thousands of years ago) she could do nothing but run from the many battlefields to continue in her studies.
Her luck run out when she found herself trapped in a natural grotto during the final act of the war.
Being hit in her gem as the blinding light covered the planet, she is now stuck in this distorted form.
Distorted in body and in mind, the shy and harmless Amber became an amorphous beast using fossils as make-shift weapones and bones for her own, slaughtering gems and earthlings likewise because of her rage and her residual passion for learning.
She may not be conscious about what she is doing but she is lethal nonetheless.
Her mazy subterranean hideout is now the nightmare of whoever get caught in it.

Gem: Amber
Gem Location: left eye
Faction: Yellow Diamond (formerly), indipendent
Size: 5ft (normal), usually 11ft (now)
Attitude: shy, nerdy, rambles when nervous (normal), dangerous and silent, prefers to slice or pierce to kill opponents, short attention span
Weapon: N/A, fossils, slime
Special: electricity absorbtion and channeling, immune to piercing and slicing physical damage due to amorphous slimy body, some gems she 'poofed' are still intact but cannot reform being trapped in her body
Known fusions: N/A


P.S. Sorry for the eventual grammar error, english is not my main language.