diff --git a/README.md b/README.md
index 2d15516e..5a8f2b09 100644
--- a/README.md
+++ b/README.md
@@ -172,6 +172,7 @@
 * Weapon is taken when overheated
 
 ### Sliquifier
+* Added upgraded version
 * Kills on any round (normally stops killing after round 100)
 * Removed additional goo created by chain kills
 
diff --git a/scripts/zm/_zm_reimagined.gsc b/scripts/zm/_zm_reimagined.gsc
index fb46b8b9..50feb64a 100644
--- a/scripts/zm/_zm_reimagined.gsc
+++ b/scripts/zm/_zm_reimagined.gsc
@@ -207,6 +207,8 @@ post_all_players_spawned()
 	level.equipment_subwoofer_needs_power = 0;
 	level.limited_weapons["ray_gun_zm"] = undefined;
 	level.limited_weapons["raygun_mark2_zm"] = 1;
+	level.zombie_weapons["slipgun_zm"].upgrade_name = "slipgun_upgraded_zm";
+	level.zombie_weapons_upgraded["slipgun_upgraded_zm"] = "slipgun_zm";
 	level.zombie_vars["emp_stun_range"] = 420;
 	level.zombie_vars["slipgun_reslip_rate"] = 0;
 	level.zombie_ai_limit_screecher = 1;