diff --git a/wadsrc/static/zscript/actors/inventory/powerups.zs b/wadsrc/static/zscript/actors/inventory/powerups.zs
index 157fab1b2..f3fed4b7b 100644
--- a/wadsrc/static/zscript/actors/inventory/powerups.zs
+++ b/wadsrc/static/zscript/actors/inventory/powerups.zs
@@ -569,7 +569,7 @@ class PowerInvisibility : Powerup
 		Super.DoEffect();
 		// Due to potential interference with other PowerInvisibility items
 		// the effect has to be refreshed each tic.
-		double ts = (Strength / 100) * (special1 + 1);
+		double ts = (Strength / 100.) * (special1 + 1);
 		
 		if (ts > 1.) ts = 1.;
 		let newAlpha = clamp((1. - ts), 0., 1.);