This is How Harry and his friends joined our Heroes in Weekenders Adventures of LEGO Dimensions.

Everyone is happy that they got their Potions and their items are back

Tino: Everything in Hogwarts is back.

Slughorn: Listen here, Harry Potter. You got everything back from the Death Eaters, as well. And for that, I'm very grateful. But please promise you won't be late for you next class! And even though. Don't even think about make some Potion from my office.

Harry Potter: Don't worry, I won't. And I think I could use some help for you. You must be tired from all the Potion's you make. And- I wouldn't mind a second chance to make some potion from myself right.

Slughorn: (Sigh) Yes. Making Potion can be tired. But let me feel you Something, Harry. Seeing the happy faces of all the Student like your friends, when they discover how you use some magic and Spell like us, and this time they will know what it takes to be Wizard. And you, Harry- you always look after your friends and your heart. What if something tried to take all of that away form you? We both have very important things to do, Harry. Mine is to take care of Hogwarts, and yours is to take care of your friends. So we each have to do the very best we can. After all, you're the hero of hogswarts- Harry Potter. The Famous Chosen One. The True Wizard! And even though you're parents will be proud of you, Harry... and Hogwarts is your home. Don't you see? Students rely on both of us to do our jobs. Hogwarts needs your attention... and I know Hogsmeade needs mine- urgently.

Harry Potter: You're right. I am the True Wizard of Hogwarts! And if Hogwarts got some trouble, they always need my help. And I can help everyone in Hogwarts!

Ron: That's the Spirit, Harry. Come on, let's go with them.

Tino: Alright, everyone, let's go.

Dumbledore: Hold On, Laval. I need to tell you something.

Laval: What is it, Professor?

Dumbledore: Don't you have a Dream that you want to see Other Worlds just like Tino and his friends?

Laval: It's because, a kid told me in a dream.

Dumbledore: Laval, you and your friends will have your own Adventure throughout your Journey. No Matter what. You and your friends will do this Adventures on your own.

Laval: I will but... How can I do that?

Dumbledore: Just Follow your heart, no matter what happens, you will know when the time has begun.

Laval: Right.

They went to the Portal

Laval is wondering

Laval: Who is that boy?

Flashback has started

Laval in Land of Departure and he saw Ventus and Aqua looking at the Stars

Laval: Who are those two?

Ven: Y'ever wonder what stars are? Where light comes from?

Aqua: Hmm... Well, they say-

Terra: That Every star up there is another world.

They saw Terra

Aqua: Terra.

Terra: Yep, Hard to believe there are so many worlds out there besides our own. The light is their hearts, and it's shining down on us like a million lanterns.

Laval: Hey, guys!

He went pass through him, and he realises they there were an Illusion from his dream

Laval: Huh?

Ven: What? I don't get it.

Terra: In other words, they're just like you, Ven.

Ven: What does that mean?

Terra: You'll find out someday, I'm sure.

Ven: I want to know now.

Terra: You're to young to know.

Ven: Quit treating me like a Kid.

Then Aqua Laugh

Terra: Hey, what are you laughing at?

Aqua: I can't help it. You two would make the weirdest brothers.

Then began to Laugh

Laval: That's Hilarious.

They all look at the stars

Aqua: Oh yeah, Terra, you and I have our Mark of Mastery exams tomorrow.

She show them three Way finder

Aqua: I made us Good luck Charm

Laval saw them

Laval: Those look like the ones back in Chima.

Aqua give them to Terra and Ven

Ven: Wow! I get one, too?

Aqua: Of course, one for each of us. Somewhere out there, there's a tree with star-shaped fruit... and the fruit represents an unbreakable connection. So as long as you and your friends carry good luck charms shaped like it, nothing can ever drive you apart. You'll always find your way back to each other. Technically, I think you're supposed to make them with seashells, but I did the best with what I had.

Terra: Oy, sometimes you are such a girl.

Aqua: Hey, what do you mean, "sometimes"?

Ven: So this isn't a real good luck charm?

Aqua: Well, that's yet to be seen. But I did my work a little magic on it.

Ven: Really? Like what?

Aqua: An Unbreakable Connection.

Laval: What does it mean?

Hours later

Terra: Hey, we're heading back.

Ven: Yeah, me too.

He went to the Others, And Aqua is looking at the star

Aqua: Together... always.

She went to the Others

Aqua, Terra & Ven: That would be the last night we ever spent, beneath the same stars.

Laval: Till all are one.

End of Flashback

Laval: Those three they were look like Me, Cragger and Eris... But... I wonder what happened to them? (Sigh) Maybe... Maybe, I find them someday.