Name: Explosive Opal
Nicknames, Aliases, etc: Opal - her full name is barely known to anyone but herself (and maybe Thrill Seeker, because she swears that mare knows everything).
Gender: Female
Sexuality: "Eh," quoth Opal; heterosexual and probably won't ever be looking.
Species: Earth
Alliances: Part of the Explorers' Guild, though she never actually does much exploring. Mostly, she just sits around and investigates anything the others bring to her.
Appearance: Opal's fur is dark, muted purple; her mane and tail are a lighter version of that same colour. It's straight by nature, and she makes sure it's as neat as possible. That, unfortunately, is just limited to "don't let it get in the way". Its natural volume doesn't help. She's unsurprisingly thin, in a way that makes her look starving and weak rather than beautiful. Her eyes are amber, and almost always narrowed.
Kin: -
Other relationships: -
Strengths: Opal's strengths are confined primarily to her mind. She has good memory, capable of memorising things within minutes - seconds, if it's simple - and dredging them up even after months. She's generally a good planner and quick thinker - she can visualise, calculate, and reason things out in her head, no paper needed.
Weaknesses: Opal's weak, for an Earth pony. She's could still beat the average unicorn or pegasus, but not a fellow Earth. Her planning skills stop where other people are involved: she tends to assume they'll act the same way she would, rather than taking into account their personality, and her plans reflect this. In general, she's terrible at reading people. She's been trying to get better with this, but she's never really succeeded.
Overall: Opal's rather cautious. She thinks her ideas over carefully before voicing them, lest she miss some lethal flaw within them. She's a very harsh critic, especially to herself; while she knows perfection is unrealistic, she strives to come as close as possible. It takes a lot to offend or faze her. Hardworking and devoted, she takes work seriously, often sacrificing sleep to work on some project or another. She's extremely honest, valuing truth above all else, and would never lie just to save her own skin. It's perhaps for this reason that she's so bad at detecting others' lies. She has a tendency to assume others would react to situations the same way she would - with the truth.

Opal adapts easily to change, being as flexible as she is. She'll almost instantly accept new things, as long as she believes it's for the better. This can cause her to seem disloyal, abandoning her allies as soon as someone challenges them, but she thinks of it as an attribute rather than a flaw - would you rather hang on stubbornly to outdated beliefs, or allow yourself to change and grow?

She has a naturally solemn disposition, with a measured gait and ever-neutral face. This isn't usually a conscious attempt to be stoic; she's just terrible at expressing herself. She could be frantic with anxiety on the inside, but the only physical indication of such would be a few twitches of her hooves, or slightly furrowed eyebrows. Less perceptive ponies seldom figure out what she's feeling, unless she explains herself verbally. An introvert, Opal prefers to be alone as opposed to with other ponies. She doesn't go out of her way to avoid them, but given the choice between trying to hold a conversation with somebody and not doing so, she'll choose the latter. Some would say that Opal is somewhat fuzzy where morals go - she doesn't mind manipulating people, or bending the rules if she has a decent reason. However, she has justifications for all of these.