My backstory.

[Froogleyboy]

I'm trying to come up with a back story for my troglodyte. Plz add suggestions.
So far this is what I have:

When Spike was VERY young he went hunting with his mother off the coast of mexico. He seen omething shiny and swam toward it when a large net caught him up. He was dragged on to a boat along with many fish. Two Mexican fisherman stared at him for a long time and had a long conversation in spanish before deciding to keep him. They were thinking about what to call him when they seen his pitch black eyes and they called him sullivan (Dark eyes.)
Through the years the mexicans abused Sullivan and forced him to work as a slave. One day (Close to his 17th B-Day) Sullivan had a thought. When the mexicans asked for a beer he went to the closet ,got some bleach and poured it into the cups. When he was taking it to the Mexicans he got nervous started to stink (see the Stench ability on troglodytes MM page) and the mexicans got angry. He suddenly reached on the counter for a fish skinning knife and stabbed the mexicans.
Sully ran for the streets and never looked back. He has dodged the law and stolen to fill his belly for his whole life. He has never trusted a soul again. forever a loner.

[Prometheus]

Hmm, I remember you and your trog. Ideas:

Put someone who has been kind to poor old Sullie (preferably a Mexican, less he develop as a racist), but you'd make it clear that he is unable to take advantage of that kindness (say a girl he met while he was enslaved and therefore he was unable to see again or explain) or unable to trust (someone who had earlier offered to help him betray his slavers, but Sullie thought it might be a trap for him). This opens the door for human interaction, but puts it on strange or uncertain terms.

You will also need a more long term goal, I think. While Sullie may simply be focused on dodging the law and filling his belly right now, if he is an adventurer he will have considerably more tools at his disposal in his journey. Perhaps his plan is simplistic, like traveling to the Bahamas because he believes people are free and happy (maybe he saw an advertisement somewhere). If that is the plan and he reaches the Bahamas (or wherever), than you have a moment of character growth where he has to realize what he really wants. Or you could have an unattainable goal from the beginning, like dismantling the US government, killing the last member of the Mexican gang, finding his parents, or transforming into a human.

Also, he should either hate or love the shiny thing he picked up. Whichever it is, the shiny thing should have attribute of the opposite (i.e. hates the diamond ring or loves the shred of a coke-la-cola bottle). In either case, he should keep it with him and perhaps hold a superstitious value in it.

[Froogleyboy]

Have anymore ideas for goals?

[Prometheus]

Really it depends a lot on a) the plot of the d20 Modern setting/campaign and b) what the personality of your character will focus on. That said, here's what I'm thinking based on the information you have.

Because you have humble beginnings, and you have already mentioned how early trauma has begun to shape your mode of thinking for the rest of your life (being a loner), it makes sense that you would fixate on a small detail of those events and extrapolate it to absurd proportions. At least until your character reaches some kind of turning point, in which your character fully overcomes the tragedy of the past and begins his life with a new focus on the future (this could occur early on, in the middle, or the very end - pretty much whenever you feel bored of your goal, when you accomplish it, or when it is appropriate to the plot). The post-turning point goal (if there is one) should be something you decide when it approaches.

So on fixating on the details of the past, one way to do this is to take an emotion and have it dominate in the context of the past-
Anger: kill that mexican, Kill those mexicans, kill all Mexicans, kill the police, kill the government, kill all humans.
Fear: trust nobody, gain perfect self-protection, learn "the secrets" of the government.
Jealousy: emulate humankind, gain street-power, gain corporate-power, become human, get a human love interest.
Loneliness: find your parents, find someone who was kind to you,find your shiny thing, find a humanoid to love you, find a trog to love you, find trogs in general, get rich enough to buy sex, make yourself irresistible attractive.

Now, because you are so screwed up, you might not openly admit any of these goals and you might even pursue them in a counterproductive fashion. Indeed, your real conflict may be with yourself. Or maybe it is so grand that it is truly a powerful undertaking.

Ordinarily I add "you met a girl while you were a slave and went after her to find her the rest of the campaign", but that is already the plot of a lot (a LOT) of movies.

[Froogleyboy]

UPDATE: During his slave years he met a young girl named Maria. Maria was also a slave. They became friends and plotted against theyre masters. (She came up with the poisoning plan) they had planned to run off together but a neighbor heard the mexicans scream and called the cops. Sully quickly gave her a fake ID he had been making. They ran opposite ways, Maria running further into mexico and Sully ran to america.

[Canadian]

Are you a Mexi can? or a Mexi Can't?

[Froogleyboy]

WHAT?! Thats stupid

[hewhosaysfish]

Troglodyte? Mexico?
Buh?

[Tsotha-lanti]

Troglodyte? Mexico?
Buh?

D20 Modern, I presume. Not that he ever specifies this in any of his threads, really.