After hours of reading and searching for information in his library Mark finally found what he was looking for...
A ritual to enter the zero dimension...
Nor!Sans , Mark!Papyrus and ???!Grillby belongs to me

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After hours of reading and searching for information in his library Mark finally found what he was looking for...
A ritual to enter the zero dimension...
Nor!Sans , Mark!Papyrus and ???!Grillby belongs to me
Excuse me Mr Fox, if this isn't too spoiler to answer.... Why are the future versions of the boys here?
Like what did they come for? Are they looking for something or someone? And why did they have to knock them out why not just ask them?
Again if this is too spoilery you don't have to answer.
Don't worry, they are very good questions, well they are here to rescue these little demons
they are Hely ((the future daughter of Jasar and Gim)) and Keo ((the future son of Nor and Yosa)))
they tried to cast a spell to see their grandfather through a time window because they wanted to know him ((because for some reason they don't want to talk about him with them))
But it went wrong and they ended up going back in time and freeing some villains from
"the mirror"
The comic that explains it
And their parents obviously wouldn't leave them alone and go after them,???!Grillby allowed them to return in good time with several conditions:
1- Don't interfere with the past ((that's why they can't just ask them)))
2- Kill the villain boss ((Villain!Gaster))
3- That Mark going to talk to her personally about something important
That's why, with the help of a spell, they went back to time and replaced their present versions, using a protective stamp :
The stamp hides scars, prostheses, etc... but one thing it doesn't hide is a pregnancy , yep , Gim is pregnant and when she found out, was already on the mission and can't return home for now
and while they are in charge of looking for their children ((which by the way a good punishment awaits them xd)), Mark is in charge of talking to ???!Grillby
But here the question is... who is ???!Grillby
And
Who are those villains?
I won't say more because that it's Spoiler
I only put the most important parts here ╮(─▽─)╭
The complete comics related to this have the tag #Underblood future events
;3