Frisk was in a regular genocidal route when CROSS showed up and the same way xtale!chara thought that cross was week enough that he would be distracted easily, xtale!chara posessed undertale!frisk's body and began slicing so many monster on various universes...
glitchtale!gaster
glitchtale!sans
glitchtale!chara
underswap!papyrus
underswap!sans
underswap!chara
underfell!asgore
underfell!sans
underfell!papyrus
nightmaretale!sans (Nightmare)
And after killing absorving all those souls + the souls of the regular monsters...
xtale!chara created a new universe called Realtale.
With their powers they created everything... The underground, the surface, their own realtale!sans and realtale!papyrus... It was awesome...
But realtale!sans knew something was going on, and with his magic he went back in time, and see what "realtale!frisk" has being doing.
HE SAW THEM KILLING AND ABSORVING EVERYONE'S SOULS...
HE THOUGHT IT WAS A REGULAR GENOCIDE PATH BUT WHEN THEY TRIED TO STOP THEM...
THAT HADN'T BEEN THE FIRST TIME THEY KILLED THE WHOLE UNDERGROUND...
THEY HAD ATTACKS SMIMILAR TO HIS
THEIR DETERMINATION WAS UNSTABLE...
realtale!sans went back into reality, and tried to kick xtale!chara's soul out of undertale!frisk's body...
With that, undertale!frisk was in control again and realtale!sans explained everything to them...
And that's how the Realtale universe was created...
However... undertale!frisk was glitched and had to become part of the new universe, becoming realtale!frisk.
They had 7 different parts of his soul.
And had great power in their posession.
areudirty
snowghoul
theartofmadeline
dededos