Fixes free chemsplosion reagent purging by replacing it with the same thing but dangerous

code/modules/reagents/chemistry/recipes.dm

@@ -281,7 +281,7 @@
  * * modifier - a flat additive numeric to the size of the explosion - set this if you want a minimum range
  * * strengthdiv - the divisional factor of the explosion, a larger number means a smaller range - This is the part that modifies an explosion's range with volume (i.e. it divides it by this number)
  */
-/datum/chemical_reaction/proc/default_explode(datum/reagents/holder, created_volume, modifier = 0, strengthdiv = 10)
+/datum/chemical_reaction/proc/default_explode(datum/reagents/holder, created_volume, modifier = 0, strengthdiv = 10, clear_mob_reagents)
 	var/power = modifier + round(created_volume/strengthdiv, 1)
 	if(power > 0)
 		var/turf/T = get_turf(holder.my_atom)
@@ -300,8 +300,29 @@
 		var/datum/effect_system/reagents_explosion/e = new()
 		e.set_up(power , T, 0, 0)
 		e.start(holder.my_atom)
-	holder.clear_reagents()
-
+	if (ismob(holder.my_atom))
+		if(!clear_mob_reagents)
+			return
+		// Only clear reagents if they use a special explosive reaction to do it; it shouldn't apply
+		// to any explosion inside a person
+		holder.clear_reagents()
+		if(iscarbon(holder.my_atom))
+			var/mob/living/carbon/victim = holder.my_atom
+			var/vomit_flags = MOB_VOMIT_MESSAGE | MOB_VOMIT_FORCE
+			// The vomiting here is for effect, not meant to help with purging
+			victim.vomit(vomit_flags, distance = 5)
+		// Not quite the same if the reaction is in their stomach; they'll throw up
+		// from any explosion, but it'll only make them puke up everything in their
+		// stomach
+	else if (istype(holder.my_atom, /obj/item/organ/internal/stomach))
+		var/obj/item/organ/internal/stomach/indigestion = holder.my_atom
+		if(power < 1)
+			return
+		indigestion.owner?.vomit(MOB_VOMIT_MESSAGE | MOB_VOMIT_FORCE, lost_nutrition = 150, distance = 5, purge_ratio = 1)
+		holder.clear_reagents()
+		return
+	else
+		holder.clear_reagents()
 /*
  *Creates a flash effect only - less expensive than explode()
  *

code/modules/reagents/chemistry/recipes/pyrotechnics.dm

@@ -1,13 +1,48 @@
+#define PURGING_REAGENTS list( \
+	/datum/reagent/medicine/c2/multiver, \
+	/datum/reagent/medicine/pen_acid, \
+	/datum/reagent/medicine/calomel, \
+	/datum/reagent/medicine/ammoniated_mercury, \
+	/datum/reagent/medicine/c2/syriniver, \
+	/datum/reagent/medicine/c2/musiver \
+)
+
 /datum/chemical_reaction/reagent_explosion
 	var/strengthdiv = 10
 	var/modifier = 0
 	reaction_flags = REACTION_INSTANT
 	reaction_tags = REACTION_TAG_EXPLOSIVE | REACTION_TAG_MODERATE | REACTION_TAG_DANGEROUS
 	required_temp = 0 //Prevent impromptu RPGs
-
-/datum/chemical_reaction/reagent_explosion/on_reaction(datum/reagents/holder, datum/equilibrium/reaction, created_volume)
-	default_explode(holder, created_volume, modifier, strengthdiv)
-
+	// Only clear mob reagents in special cases
+	var/clear_mob_reagents = FALSE
+
+/datum/chemical_reaction/reagent_explosion/on_reaction(datum/reagents/holder, datum/equilibrium/reaction, created_volume, clear_mob_reagents)
+	// If an explosive reaction clears mob reagents, it should always be a minimum power
+	if(ismob(holder.my_atom) && clear_mob_reagents)
+		if(round((created_volume / strengthdiv) + modifier, 1) < 1)
+			modifier += 1 - ((created_volume / strengthdiv) + modifier)
+	// If this particular explosion doesn't automatically clear mob reagents as an inherent quality,
+	// then we can still clear mob reagents with some mad science malpractice that shouldn't work but
+	// does because omnizine is magic and also it's the future or whatever
+	if(ismob(holder.my_atom) && !clear_mob_reagents)
+		// The explosion needs to be a minimum power to clear reagents: see above
+		var/purge_power = round((created_volume / strengthdiv) + modifier, 1)
+		if(purge_power >= 1)
+			var/has_purging_chemical = FALSE
+			// They need one of the purge reagents in them
+			for(var/purging_chem as anything in PURGING_REAGENTS)
+				if(holder.has_reagent(purging_chem))
+					// We have a purging chemical
+					has_purging_chemical = TRUE
+					break
+			// Then we need omnizine! MAGIC!
+			var/has_omnizine = holder.has_reagent(/datum/reagent/medicine/omnizine)
+			if(has_purging_chemical && has_omnizine)
+				// With all this medical "science" combined, we can clear mob reagents
+				clear_mob_reagents = TRUE
+	default_explode(holder, created_volume, modifier, strengthdiv, clear_mob_reagents)
+
+#undef PURGING_REAGENTS
 /datum/chemical_reaction/reagent_explosion/nitroglycerin
 	results = list(/datum/reagent/nitroglycerin = 2)
 	required_reagents = list(/datum/reagent/glycerol = 1, /datum/reagent/toxin/acid/nitracid = 1, /datum/reagent/toxin/acid = 1)
@@ -104,11 +139,18 @@
 /datum/chemical_reaction/reagent_explosion/penthrite_explosion_epinephrine
 	required_reagents = list(/datum/reagent/medicine/c2/penthrite = 1, /datum/reagent/medicine/epinephrine = 1)
 	strengthdiv = 5
+	// Penthrite is rare as hell, so this clears your reagents
+	// Will most likely be from miners accidentally penstacking
+	clear_mob_reagents = TRUE
+
 
 /datum/chemical_reaction/reagent_explosion/penthrite_explosion_atropine
 	required_reagents = list(/datum/reagent/medicine/c2/penthrite = 1, /datum/reagent/medicine/atropine = 1)
 	strengthdiv = 5
 	modifier = 5
+	// Rare reagents clear your reagents
+	// Probably not good for you because you'll need healing chems to survive this most likely
+	clear_mob_reagents = TRUE
 
 /datum/chemical_reaction/reagent_explosion/potassium_explosion
 	required_reagents = list(/datum/reagent/water = 1, /datum/reagent/potassium = 1)