diff --git a/changelog.txt b/changelog.txt
index 636db31..5e8c4a9 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -1,4 +1,16 @@
 ---------------------------------------------------------------------------------------------------
+Version: 0.0.20
+Date: 2022-08-18
+  Fixes:
+    - Fix multiple prerequisite issue
+---------------------------------------------------------------------------------------------------
+Version: 0.0.19
+Date: 2022-08-18
+  Features:
+    - Menu simulation
+  Changes:
+    - Minor nanobot tech tree tweak
+---------------------------------------------------------------------------------------------------
 Version: 0.0.18
 Date: 2022-08-17
   Changes:
diff --git a/data-final-fixes.lua b/data-final-fixes.lua
index 5e6627a..67c7eaa 100644
--- a/data-final-fixes.lua
+++ b/data-final-fixes.lua
@@ -43,6 +43,7 @@ if not mods.bzaluminum and not mods.bzcarbon then
   util.replace_ingredients_prior_to("electronics", "electronic-circuit", "copper-cable", 2)
 end
 
+util.add_prerequisite("nanobots", "electronics")
 util.remove_ingredient("small-lamp", "blank-circuit") -- mod mash
 
 -- Should come as late as possible, doesn't need to be last
diff --git a/data.lua b/data.lua
index 3fa3618..26625fe 100644
--- a/data.lua
+++ b/data.lua
@@ -6,6 +6,7 @@ require("prototypes/bakelite")
 require("prototypes/basic-chemical-plant")
 require("prototypes/k2-recipe")
 require("prototypes/se-recipe")
+require("gas-sim")
 
 local util = require("data-util");
 
diff --git a/gas-sim.lua b/gas-sim.lua
new file mode 100644
index 0000000..e831c70
--- /dev/null
+++ b/gas-sim.lua
@@ -0,0 +1,25 @@
+
+-- For testing only
+-- local kept1 = false
+-- for name in pairs(data.raw["utility-constants"]["default"].main_menu_simulations) do
+--   if kept1 then
+--     data.raw["utility-constants"]["default"].main_menu_simulations[name] = nil
+--   end
+--   kept1 = true
+-- end
+
+data.raw["utility-constants"]["default"].main_menu_simulations["gas-rig"] = {
+  checkboard = false,
+  save = "__bzgas__/menu-simulations/gas-rig-sim.zip", length = 15*60,
+  init =
+  [[
+    local logo = game.surfaces.nauvis.find_entities_filtered{
+      name = "factorio-logo-16tiles", limit = 1}[1]
+    game.camera_position = {logo.position.x, logo.position.y+14}
+    game.camera_zoom = 0.75
+    game.tick_paused = false
+    game.surfaces.nauvis.daytime = 0
+  ]],
+  update = [[]]
+}
+
diff --git a/info.json b/info.json
index 5dd4276..1217ccd 100644
--- a/info.json
+++ b/info.json
@@ -1,6 +1,6 @@
 {
     "name": "bzgas",
-    "version": "0.0.19",
+    "version": "0.0.20",
     "factorio_version": "1.1",
     "title": "Natural Gas",
     "author": "Brevven",
diff --git a/menu-simulations/gas-rig-sim.zip b/menu-simulations/gas-rig-sim.zip
new file mode 100644
index 0000000..8741573
Binary files /dev/null and b/menu-simulations/gas-rig-sim.zip differ