diff --git a/rules.ini b/rules.ini
index 703d0ba..78f0035 100644
--- a/rules.ini
+++ b/rules.ini
@@ -1433,15 +1433,16 @@ ActiveAnimDamagedFrames=41
 
 ; Pirsm Tower
 [GGPRIS]
+Prerequisite=weap
 Primary=PrismZap
-Strength=400
+Strength=300
 Armor=heavy
 TechLevel=1
 Sight=8
 Owner=allies
-Cost=5
+Cost=1000
 Points=80
-Power=-10
+Power=-120
 Ammo=3
 Powered=true
 Sensors=yes