Minecraft Wiki
Java Edition 18w31a.png

Java Edition



Release date

August 1, 2018

Snapshot for



Client (.json)

Protocol version


Data version


18w31a[1] is the third snapshot released for Java Edition 1.13.1, which adds some new features, changes some existing features, optimizes performance, and fixes many bugs.



  • Added a concept of force-loaded chunks to the game, and a command (/chunk) to toggle force-loading on and off.
Block tags
  • Added the block tag minecraft:underwater_bonemeals.



  • Are now properly waterlogged.


  • Now have a 5% chance of dropping bone meal when killed.
  • Now spawn only in rivers, oceans, or beaches.


Bone meal
  • When used in water of warm ocean biomes, it now has a chance to grow coral.

Command format[]

  • The scoreboard operator %= was changed from using Java's native % to using Math.floorMod. This causes the operator to use floored modulo instead of truncated modulo, so now -1 % 7 wraps to 6 instead of returning -1.[2]
  • Line numbers in function parse error logs now start with 1 (was 0).


  • Performance has been optimized.


45 issues fixed
From released versions before 1.13
  • MC-73 – Green arrow bug on maps in frames.
  • MC-1528 – Maps in item frames' markers aren't persistent.
  • MC-96998 – End Cities / Woodland Mansions don't generate completely when interrupting generation
  • MC-112801 – Players on the death screen still cause spawners to spawn.
  • MC-122939 – Statistics for mining banners and beds never increase.
  • MC-128547 – Minecraft keeps previously used World in memory if the player has hit any entity in that world.
From 1.13
  • MC-121369 – Holding ESC while clicking "Multiplayer" returns user to main menu
  • MC-123021 – Crash on open if "Saves" is a link
  • MC-124583 – Cannot place structure void block next to another when right clicking on one
  • MC-125337 – When the double-held trident throws, players will lift both hands
  • MC-130258 – Maps in item frames show shading problems.
  • MC-131397 – Sponges cannot remove water from conduits
  • MC-132451 – Command Parser - invalid value for block property and property name are reversed in error message
  • MC-132769 – Detecting a 2 redstone tick repeater with an observer block creates a 2 redstone tick pulse
  • MC-133181 – Observer's cooldown is broken.
  • MC-133546 – Player becomes "ghost" when dying in the nether or going through the end portal back to the overworld
  • MC-134105 – Can't return from the end after defeating dragon.
  • MC-134159 – Saved world causes crash in 1.13.
  • MC-134667 – Async Chunk Gen dangerously adding entities to world async.
  • MC-134889 – Iron golems spawn in air blocks.
  • MC-134916 – Sound event block.pumpkin.carve doesn't play when carving normal pumpkins.
  • MC-135049 – Old world doesn't save map markers in 1.13.
  • MC-135261/setblock for player heads don't show the texture after the placement.
From the 1.13.1 development versions
  • MC-134816 – Crash: Exception ticking world entities
  • MC-134825 – Tab completion/suggestions don't work for some non-literal arguments (in chat)
  • MC-134832 – TNT with unstable=true blockstate is ignited instead of broken in creative mode.
  • MC-134898 – Pressing Escape no longer returns to main menu from singleplayer menu.
From the previous development version
  • MC-134966 – Using /setblock to place an "Always Active" command block with a command won't execute the command immediately
  • MC-134967NullPointerException when placing Wither Skeleton Skulls.
  • MC-134974 – Entities in your world can randomly freeze
  • MC-134982 – Exception when placing a command block.
  • MC-134987 – Renaming a world doesn't update its name until re-entering the world list.
  • MC-134988 – Optimizing a world doesn't update it until re-entering the world list.
  • MC-135039 – The game crashes when /setblock-ing a spawner with an entity ID containing capital letters
  • MC-135053 – Sticky pistons get stuck when receiving a 0 gametick pulse.
  • MC-135136 – Crash when placing a chain command block with set command.
  • MC-135147 – Loading/saving structures with command blocks in them causes errors
  • MC-135172 – Under certain conditions pistons can't be powered for the first 2 gameticks after being moved.
  • MC-135185 – All redstone components can become stuck in a powered state when indirectly unpowered.
  • MC-135186 – Pistons can only be re-pulsed 5 or more gameticks later.
  • MC-135194 – Pistons react 1 gametick too late.
  • MC-135229 – Game crash when opening Furnace
  • MC-135268 – Switching to spectator mode and back creates ghost player duplicates for other players
  • MC-135293 – Profiler doesn't exit section when an entity is removed, causing recursive profiling and lag
Private issues
  • MC-134716 – Minecraft Multiplayer – Player kick exploit.[1]


Video made by slicedlime:


  • This snapshot, being the third for 1.13.1, was released in the same week of the year as the third snapshot for 1.9, 15w31c.
  • 18w31a was released exactly 6 years after 1.3.1.