Street Gods: Magic Hole, Depth based Wizardry

We had a requirement on Street Gods to have a reveal when the Boss Tile appears on the Tafl Board (the object which you place the tiles on, seen in the videos), the object needed to appear from inside a fiery pit, which was not visible to the outside viewer, and in addition the "Boss Cube" must be able to cross the threshold of the hole into the rest of the 3D scene.
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We've seen similar done with 3D card battler games, but nothing I have noticed in production where objects inside the card can also exist, or project through the frame into the rest of the 3D space.
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At the time of writing this box I came across Simon Trümpler's work here: https://www.artstation.com/artwork/g0g8bP - which uses similar ideas but we came at it from different angles.
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There is one small limitation to this on a floating "hole" in space, that the planes value is set at runtime for cut off so the object existing outside will still cut off if placed below the plane value outside of the hole, this isn't so much of an issue with holes in walls or non-destructive floor environment as you would not be able to see the objects inside the wall or below ground level anyway.
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Models and Textures for Tafl Board:
https://www.artstation.com/reecemccarthy

Boss Cube by:
https://www.artstation.com/pokusaika