Isaac Jones is a pilot in Into the Breach.
Location
Isaac Jones can be acquired by completing islands.
Background
Isaac has seen too many timelines collapse, and seen too many permutations for how things can go wrong - his high intelligence actually works against him, rather than makes him more confident because he can imagine all the ways things can go wrong (think Chidi Anagonye in The Good Place). He feels ill-suited for being a soldier (his squad mates usually agree, but his scientific knowledge is indispensable). While he and Bethany are technically brother and sister, there hasn't been a timeline where they both were alive to realize this (either Bethany dies at a young age, or Isaac dies - only one of them could be saved in the womb b/c of a chronic medical condition their parents had). He respects machines and sees them as equals due to being raised on Pinnacle (he has faith in Zenith, perhaps too much as he feels she's too intelligent to do anything wrong). Isaac is as much of a genius as his sister, although self-doubt weakens him. He has considerable knowledge of aeronautics, physics, gravitation theory and manipulation, and a number of other fields. It is likely Isaac could master any science he chose to, his only block is his own perceived limitations.
Personality
Paranoid & pessimistic. Generally a good person but not handling all the stress well, and his attitude can sometimes be demoralizing - he's suspicious of his own successes and victories. Definitely a "this timeline's already half-lost" kind of guy. Stutters because of temporal research studies... it's caused a nervous system problem in his speech patterns.