Timelord1963 - one hit (and correct reasoning behind it), + you are close but not quite right about Sachys.
So I made it hard for me again...
Maybe somebody wants to correct his\her guesses? How am I supposed to pick the winner now? : )
I'll probably change the one hit in a moment, but I'll to change Sachys
to The Fool
as I very nearly picked that last night (but couldn't think of a better match for misteryo's danger avatar than the cliff edge). However that fits Sachys story much better as the character later talks about falling over the edge of an abyss and a tentacled moster waiting below, exactly as your Tarot card depicts the Fool about to do.
If that's Sachys then misteryo can't also be The Fool; I would have picked The Tower to represent the danger sign but you hadn't used that. So the other thing written on his avatar is 'Men at work' which had made me think of that 'Land Down Under' song, in which case I'll pick The Hanged Man/ Selflessness for misteryo
as he sees the world upside down... Yeah, that's not right :)
I'll keep the others as they were, Niflmine = Judgement/ Rebirth
(I also thought Fallout Boy could maybe represent the child in this card if judgement day=apocalypse), ggf162 = Strength
, Chimerical = Death