From 8614f8d7ffc4faaf5be0164bd8df8d3ba8bdb012 Mon Sep 17 00:00:00 2001
From: LordME <58342752+TheLordME@users.noreply.github.com>
Date: Thu, 21 Aug 2025 16:55:25 +0200
Subject: [PATCH] fix occasional runtime related to blood mixture merging
 (#7269)

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:cl:
fix: fix occasional runtime related to blood mixture merging
/:cl:

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---
 code/modules/reagents/chemistry/reagents/blood/blood_mixture.dm | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/code/modules/reagents/chemistry/reagents/blood/blood_mixture.dm b/code/modules/reagents/chemistry/reagents/blood/blood_mixture.dm
index 8468bf05bb8..42a08550091 100644
--- a/code/modules/reagents/chemistry/reagents/blood/blood_mixture.dm
+++ b/code/modules/reagents/chemistry/reagents/blood/blood_mixture.dm
@@ -181,6 +181,8 @@
 	var/total_ratio = 0
 	for(var/key in fragment_ratios)
 		total_ratio += fragment_ratios[key]
+	if(total_ratio == 0)
+		total_ratio = 1
 	var/fixup_multiplier = 1 / total_ratio
 	for(var/key in fragment_ratios)
 		fragment_ratios[key] *= fixup_multiplier