Mo Glass

68,840 Downloads Last Updated: Sep 10, 2020 Game Version: 1.16.3

Mo Glass


Mo Glass

Adds glass stairs and glass slabs to Minecraft.



  • Glass Slabs!
  • Stained Glass Slabs! (since v1.3)
  • Glass Stairs!
  • Stained Glass Stairs! (since v1.3)
  • Working Transparency! (see below)


Seamless Transparency

Both the stairs and the slabs are see-through in the same way as vanilla glass blocks. You can place multiple stairs, slabs and full blocks next to each other and they will look like a single piece of glass.

seamless transparency


Why aren't these blocks part of vanilla Minecraft?

Before I started making this mod, I always thought that Mojang just forgot about these blocks, or that they were too lazy to add them. But now that I've added these blocks myself and spent many hours to get the transparency to work, I think I finally understand why Mojang didn't bother. Minecraft's stairs are surprisingly complex blocks and they were never meant to be made transparent. Slabs might be easy enough, but I think if Mojang added those then people wouldn't stop asking for the stairs. And glass stairs are an absolute nightmare to make.

Stairs can be placed facing North, East, South or West, they can be upside-down or right-side-up, they can be straight or curved in one of four different ways and they have six faces that may or may not be transparent, depending on what block is next to them. But here's the catch: On each of those six faces, there could be another block of glass stairs that can also be placed facing North, East, South or West, upside-down or right-side-up and either straight or curved in one of four different ways. And then of course, on each of the six faces there could also be a non-transparent block, a regular glass block or a glass slab that is either placed on the bottom half, top half, or is a double slab.

In the end, there are 10800 possible scenarios that need to be accounted for just to calculate transparency of glass stairs. But then you also have to calculate the transparency of glass slabs (810 possible scenarios) and adjust the transparency calculation of regular glass blocks (270 possible scenarios, or 258 more than before).*

That's a lot of effort just to add two new blocks to the game - and a lot of opportunities for new bugs to sneak in. That, I think, is why Mojang didn't bother.

*Here's how I got those numbers:

possible variations of stairs:

pvStairs = 4 * 2 * 5 = 40


possible variations of slabs:

pvSlabs = 3


possible variations of glass blocks:

pvGlass = 1


possible variations of non-transparent blocks:

pvBlocks = 1 (because any variations would be ignored when calculating transparency)


possible combinations combined:

pvAll = pvStairs + pvSlabs + pvGlass + pvBlocks = 40 + 3 + 1 + 1 = 45


possibly transparent faces of a block (including stairs, even though they have more faces):

f = 6


possible scenarios for transparency of stairs:

psStairs = pvAll * f * pvStairs = 45 * 6 * 40 = 10800


possible scenarios for transparency of slabs:

psSlabs = pvAll * f * pvSlabs = 45 * 6 * 3 = 810


possible scenarios for transparency of glass blocks:

psGlass = pvAll * f * pvGlass = 45 * 6 * 1 = 270


possible scenarios for transparency of glass blocks if glass stairs and slabs don't exist:

psGlassVanilla = (pvGlass + pvBlocks) * f * pvGlass = (1+1) * 6 * 1 = 12 


Crafting Recipes

Glass Slab:

glass slab crafting recipse

glass slab stonecutter recipe

Glass Stairs:

glass stairs crafting recipe

glass stairs stonecutter recipe


Supported Languages

  • English
  • German (since v1.2)
  • Chinese (Traditional) (since v1.2)
  • Chinese (Simplified) (since v1.2)
  • Spanish (Argentina) (since v1.4)
  • Spanish (Chile) (since v1.4)
  • Spanish (Ecuador) (since v1.4)
  • Spanish (Spain) (since v1.4)
  • Spanish (Mexico) (since v1.4)
  • Spanish (Uruguay) (since v1.4)
  • Spanish (Venezuela) (since v1.4)


Will you add Forge support?

No. A Forge version is not being considered due to Forge's new CoreMod policy as well as issues with the Forge community's treatment of modders.

However, the experimental Patchwork project can sometimes make Forge mods and Fabric mods work together. Depending on which other mods you use, this might work with Mo Glass.

Also, keep in mind that many former Forge mods now have Fabric versions (or have switched to Fabric entirely due to the above-mentioned issues).


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