I figured that Lifeburn's Cavern Tiles needed some sort of elevation. So I meshed together these Cavern Plateaus from different parts of the Lifeburns Cavern Tiles. They should help you display your ultimate multi-level-battles ;) I made plain versions, versions with cut-in-ladders, and versions with some minor walls/fortifications on top.
Use these together with the staircases I made: https://www.thingiverse.com/thing:3525648 This tiles allow you to build up multilevel plateaus. Keep in mind that the higher levels will just "sit loosely" on the blocks below, unless you're planning to use bases inbetween the levels (which might work better in terms of stability, but probably will look a little awkward).
Let me know how these check out for you guys! These are usable with any openforge 2.0 bases (2x2). Keep in mind that I flattened the rather rough textures on the Plateau "Blocks" so that they'll fit together more seemlessly.
EDIT: Here are the Cavern Riser Blocks that will give you even more mulitlevel dungeon options: https://www.thingiverse.com/thing:3612134 Have Fun!
I also remixed Lifeburn's Basic Cavern Tiles https://www.thingiverse.com/thing:3516425 the River Tiles https://www.thingiverse.com/thing:3517355 and the Graveyard Tiles https://www.thingiverse.com/thing:3518744 to make them Openforge 2.0 compatible, so check that out too!