I was watching MaplGalaxy’s live, when someone asked him to make Asta’s Sword (apparently it’s a sword that comes out of a grimoire). He made an animation (In MoonAnimator) and sort of manipulated a piece of glass to make half of the sword (which had various part in its model) disappear to make it actually look like it’s coming out of the book and not just appearing in the book.
Here’s the video (with start point set):
https://youtu.be/7LKRyLgYc7A?t=9584
I tried to do it myself (without an attachment, without setting the transparency in the script and without setting the sword’s parent to the player) and failed.
After removing anything unnecessary (I think it’s almost everything in the script), I tried to make it the most minimal possible so it will be easier to solve.
What am I missing? Welds? The game.Debris:AddItem(P, 2)? The parts being children of the player?
Here’s my game where I tried:
PartPartlyDisappear.rbxl (23.7 KB)
Judging from the code he has it seems like he is using Transparency at 0.999 with glass material and he makes all the parts of the sword have a transparency of 0.001.
I don’t know how it works exactly but I think that when you have two parts overlapping and one of them has glass material with 0.999 transparency and the parts inside of that are of transparency 0.001, the part with 0.001 transparency will also become transparent. Not sure if this is intended or a bug.

So I think that the sword is inside of that glass part (with 0.999 transparency) and the animation simply pulls it out of that block which gives it a nice effect where the sword comes out from “another dimension”. The glass is probably positioned right behind the book.
You should test glass material and transparency. I am sure that’s what creates this effect. I am simply connecting my previous knowledge and I’ve never actually done any tests/know how it works.
From what I’ve seen in the video, the sword is not inside the glass which makes a bit of a problem. He for loops all the sword parts in the model and changes their transparency to 0.001. I’ve also tested it and it doesn’t work.
I found a solution, the transparency of the sword should be bigger than 0.01 so I set it to 0.011 and it works now.