So. You want to know about Pyromaniac Isaac, hmm?
Well, then. Let's begin at the beginning1)2).
Before he arrived on the Island, Pyromaniac Isaac was a stuntman. He did a great many stupid and completely ridiculous things3)4)5)6)7).
Due to his numerous head injuries as a result of his actions, he doesn't remember very much else.
One day, after his girlfriend was raped and murdered, his house burned down, and he got fired, he was mugged in an alleyway as he took a shortcut to a hotel. These muggers were Network personnel. They knocked him out, dragged him to the Island by speedboat, and dumped him on the shore.
On the Island, Isaac first interacted with Ihpkmn, whom he thought was wearing a Cthulhu mask8). After screaming his head off and knocking himself out9), Isaac came to terms with the insanity of the Island.
Recently, however, he has noticed that he has become immune to being burned, and has tested his theory multiple times by setting his hands on fire deliberately. Having proven himself correct, he is determined to learn to become a pyromancer.
That was a long time ago. Since then, he's been infected10), defected11), fell in love12)13), founded the League of Unpopular Superheroes14)15), got possessed by Lythar16), unpossessed by Lythar, got the shit cut17) out of him by Hank in a war of Gods18), became a ghost after dying, unbecame a ghost19)20), and had some normal times with Heather for a while.
Then he proposed21), they had a wedding22), became a woman23)24), unbecame a woman...and is having good times with his 'froker25) wife.