Okay so the ending was supposed to be like this important event
Basically Ralz and Lun went to Gal (San' brother, King of The Underground) with a plan
That plan was to use Ralz' soul as the 7th soul needed to open the Barrier (it could be used because of Ralz' half Human half Skeleton nature)
But as Gal was about to kill Ralz, San entered the room, angry because Ralz lied to him about everything these past few weeks
San and Ralz have a big argument which ends with San breaking up with Ralz and leaving
Ralz feels guilty and Has second thoughts about the project and in the end decides that he won't give his soul to open the Barrier, Lun is kinda happy about that
In the end there are a few things to note:
Ralz and San are no longer together
San moved to his old house in the Ruins
Ralz moved to New Home to be closer to Lun and also closer to his jobs
The Skeletons are still trapped underground
There are also some alternative endings which I'm going to talk about under the cut
Good ending
This ending is the easiest to explain, no one dies, San wasn't that angry and didn't break up with Ralz, Skeletons are still trapped underground
Bad ending 1
San wasn't as quick as in the canon ending and Ralz is already dead, Gal took the souls and opened the Barrier
The Skeletons are free, but they lost Ralz
Most of them quickly get over his death, but not Thy and Lun, they miss him
Bad ending 2
Ralz is dead, but before Gal took the souls, Lun asked if he can do that, Gal let him
Lun absorbed the souls and was turned into a god, he broke the Barrier
The Skeletons are free, everyone is happy
Everyone is surprised that Lun was the one to break The Barrier and they start to treat him with respect, some even want to be his friends
But Lun can see that they just want to be friends with him, because he's popular now
Lun is sad, because a) souls turned him into a god and that's not really fun, b) Ralz is dead, c) he still doesn't have real friends
But the good thing is that they are free and that Lun can atleast talk to Ralz (to his soul) in his head
Bad ending 3
This one is the worst
Ralz is dead, but his soul doesn't work as the 7th soul
So Ralz is dead for nothing
Lun is devastated, because a) Ralz is dead, b) it's because of him, c) he miscalculated something and because of this Ralz is dead
Ralz: yeah, should i tell Gal that we're coming or did your dad do this already?
Lun: You could, because I have no idea if my father told him . . . Are you sure that you want to do this?
Ralz: yeah, like i told you, i have no future up there, i can sacrifice myself so that you can be happy . . . *He smiled at Lun*
Lun: *He sighed* You've been my greatest friend, you know? My only friend . . .
Ralz: what about Eal? weren't they your friend too? or are they more of a crush?
Lun: He is both, but they always talks about Paig when I'm around them, like they can't get over that bastard . . .
Ralz: they compare you to him?
Lun: Sometimes . . .
Ralz: don't listen to him, you've been my greatest friend too, you helped me a lot
Lun: You too . . . I seriously don't know how I'll manage to live without you
Ralz: you'll get over me, i'm not that interesting-
Lun: *He interrupted Ralz* Are you kidding me? You're the most interesting person I know, you always manage to cheer me up, to make me smile, you tell really good jokes, you know a lot about different things and before you say that you're not good looking, You Are
Ralz: *He blushed a little and chuckled* oh really? *He smiled*
Lun: Yeah
Ralz: heh, good to hear it
Lun: . . . I really can't believe it that tomorrow we'll be free . . . At your cost . . .
Ralz: don't worry about it, you'll be fine, no one will miss me
Lun: I will *He hugged Ralz*
Ralz: *He hugged back* i know, i know
Lun: *He let go of Ralz* Um . . . W-well you should probably go to Gal and tell him and then to your other job
Ralz: oh, right, the trial is today . . . that guy will probably have a death sentence
Lun: And your LV will go up again?
Ralz: probably . . .
Lun: Good Luck
Ralz: thanks, you too . . . see you tomorrow then?
Lun: Yeah, see ya . . .
Ralz: *He walked out of the Lab and began walking towards the Castle*
*Unknown to them Someone heard their conversation*