diff --git a/code/__DEFINES/flags.dm b/code/__DEFINES/flags.dm
index 15a8ed20949..d6ab9543d76 100644
--- a/code/__DEFINES/flags.dm
+++ b/code/__DEFINES/flags.dm
@@ -68,6 +68,7 @@
 #define MUTCOLORS_PARTSONLY	15	//Used if we want the mutant colour to be only used by mutant bodyparts. Don't combine this with MUTCOLORS, or it will be useless.
 #define NODISMEMBER		16
 #define NOHUNGER		17
+#define NOCRITDAMAGE	18
 
 /*
 	These defines are used specifically with the atom/movable/languages bitmask.
diff --git a/code/modules/mob/living/carbon/human/human.dm b/code/modules/mob/living/carbon/human/human.dm
index 08490c0f980..ae46a77d33f 100644
--- a/code/modules/mob/living/carbon/human/human.dm
+++ b/code/modules/mob/living/carbon/human/human.dm
@@ -843,18 +843,19 @@
 			return
 
 		src.visible_message("[src] performs CPR on [C.name]!", "<span class='notice'>You perform CPR on [C.name].</span>")
+		C.cpr_time = world.time
+		add_logs(src, C, "CPRed")
+
 		if(they_breathe && they_lung)
-			C.cpr_time = world.time
 			var/suff = min(C.getOxyLoss(), 7)
 			C.adjustOxyLoss(-suff)
 			C.updatehealth()
 			C << "<span class='unconscious'>You feel a breath of fresh air enter your lungs... It feels good...</span>"
-			add_logs(src, C, "CPRed")
 		else if(they_breathe && !they_lung)
-			C << "<span class='unconcious'>You feel a breath of fresh air... \
-				but it doesn't go anywhere...</span>"
+			C << "<span class='unconscious'>You feel a breath of fresh air... \
+				but you don't feel any better...</span>"
 		else
-			C << "<span class='unconcious'>You feel a breath of fresh air... \
+			C << "<span class='unconscious'>You feel a breath of fresh air... \
 				which is a sensation you don't recognise...</span>"
 
 /mob/living/carbon/human/generateStaticOverlay()
@@ -1005,14 +1006,32 @@
 				hud_used.healthdoll.icon_state = "healthdoll_DEAD"
 
 /mob/living/carbon/human/fully_heal(admin_revive = 0)
+	CHECK_DNA_AND_SPECIES(src)
+
 	if(admin_revive)
 		regenerate_limbs()
-	if(!getorganslot("lungs"))
-		var/obj/item/organ/lungs/L = new()
-		L.Insert(src)
-	if(!getorganslot("tongue"))
-		var/obj/item/organ/tongue/T = new()
-		T.Insert(src)
+
+		if(!(NOBREATH in dna.species.specflags) && !getorganslot("lungs"))
+			var/obj/item/organ/lungs/L = new()
+			L.Insert(src)
+
+		if(!(NOBLOOD in dna.species.specflags) && !getorganslot("heart"))
+			var/obj/item/organ/heart/H = new()
+			H.Insert(src)
+
+		if(!getorganslot("tongue"))
+			var/obj/item/organ/tongue/T
+
+			for(var/obj/item/organ/tongue/tongue_type in \
+				dna.species.mutant_organs)
+				T = new tongue_type()
+				T.Insert(src)
+
+			// if they have no mutant tongues, give them a regular one
+			if(!T)
+				T = new()
+				T.Insert(src)
+
 	restore_blood()
 	remove_all_embedded_objects()
 	drunkenness = 0
diff --git a/code/modules/mob/living/carbon/human/life.dm b/code/modules/mob/living/carbon/human/life.dm
index 99d99f6b6d6..db2397676c0 100644
--- a/code/modules/mob/living/carbon/human/life.dm
+++ b/code/modules/mob/living/carbon/human/life.dm
@@ -305,13 +305,26 @@
 					clear_alert("embeddedobject")
 
 /mob/living/carbon/human/proc/handle_heart()
-	if(!heart_attack)
-		return
-	else
-		if(losebreath < 3)
-			losebreath += 2
-		adjustOxyLoss(5)
-		adjustBruteLoss(1)
+	CHECK_DNA_AND_SPECIES(src)
+	var/needs_heart = (!(NOBLOOD in dna.species.specflags))
+	var/we_breath = (!(NOBREATH in dna.species.specflags))
+
+	if(heart_attack)
+		if(!needs_heart)
+			heart_attack = FALSE
+		else if(we_breath)
+			if(losebreath < 3)
+				losebreath += 2
+			adjustOxyLoss(5)
+			adjustBruteLoss(1)
+		else
+			// even though we don't require oxygen, our blood still needs
+			// circulation, and without it, our tissues die and start
+			// gaining toxins
+			adjustBruteLoss(3)
+			if(src.reagents)
+				src.reagents.add_reagent("toxin", 2)
+				src.reagents.reaction(src, INJECT)
 
 /*
 Alcohol Poisoning Chart
diff --git a/code/modules/mob/living/carbon/human/say.dm b/code/modules/mob/living/carbon/human/say.dm
index 047f46481c0..32a5b9c694f 100644
--- a/code/modules/mob/living/carbon/human/say.dm
+++ b/code/modules/mob/living/carbon/human/say.dm
@@ -48,7 +48,10 @@
 	return real_name
 
 /mob/living/carbon/human/IsVocal()
-	if(!getorganslot("lungs"))
+	CHECK_DNA_AND_SPECIES(src)
+
+	// how do species that don't breathe talk? magic, that's what.
+	if(!(NOBREATH in dna.species.specflags) && !getorganslot("lungs"))
 		return 0
 	if(mind)
 		return !mind.miming
diff --git a/code/modules/mob/living/carbon/human/species.dm b/code/modules/mob/living/carbon/human/species.dm
index e8f53b42a3a..068289e0dd7 100644
--- a/code/modules/mob/living/carbon/human/species.dm
+++ b/code/modules/mob/living/carbon/human/species.dm
@@ -128,6 +128,21 @@
 		C.regenerate_limbs() //if we don't handle dismemberment, we grow our missing limbs back
 	if(exotic_blood)
 		C.reagents.add_reagent(exotic_blood, 80)
+
+	var/obj/item/organ/heart/heart = C.getorganslot("heart")
+	var/obj/item/organ/lungs/lungs = C.getorganslot("lungs")
+	var/obj/item/organ/appendix/appendix = C.getorganslot("appendix")
+
+	if(NOBLOOD in specflags && heart)
+		heart.Remove(C)
+		qdel(heart)
+	if(NOBREATH in specflags && lungs)
+		lungs.Remove(C)
+		qdel(lungs)
+	if(NOHUNGER in specflags && appendix)
+		appendix.Remove(C)
+		qdel(appendix)
+
 	for(var/path in mutant_organs)
 		var/obj/item/organ/I = new path()
 		I.Insert(C)
@@ -471,7 +486,13 @@
 	H.apply_overlay(BODY_FRONT_LAYER)
 
 /datum/species/proc/spec_life(mob/living/carbon/human/H)
-	return
+	if(NOBREATH in specflags)
+		H.setOxyLoss(0)
+		H.losebreath = 0
+
+		var/takes_crit_damage = (!(NOCRITDAMAGE in specflags))
+		if((H.health < config.health_threshold_crit) && takes_crit_damage)
+			H.adjustBruteLoss(1)
 
 /datum/species/proc/spec_death(gibbed, mob/living/carbon/human/H)
 	return
@@ -1184,11 +1205,10 @@
 			H.adjustOxyLoss(HUMAN_MAX_OXYLOSS)
 			if(!lungs)
 				H.adjustOxyLoss(1)
-			H.failed_last_breath = 1
-		else
+		else if(!(NOCRITDAMAGE in specflags))
 			H.adjustOxyLoss(HUMAN_CRIT_MAX_OXYLOSS)
-			H.failed_last_breath = 1
 
+		H.failed_last_breath = 1
 		H.throw_alert("oxy", /obj/screen/alert/oxy)
 
 		return 0
diff --git a/code/modules/reagents/chemistry/reagents/toxin_reagents.dm b/code/modules/reagents/chemistry/reagents/toxin_reagents.dm
index 5bfe942374d..966481e1b2d 100644
--- a/code/modules/reagents/chemistry/reagents/toxin_reagents.dm
+++ b/code/modules/reagents/chemistry/reagents/toxin_reagents.dm
@@ -89,14 +89,21 @@
 	toxpwr = 0
 
 /datum/reagent/toxin/lexorin/on_mob_life(mob/living/M)
-	M.adjustOxyLoss(5, 0)
+	. = TRUE
+	var/mob/living/carbon/C
 	if(iscarbon(M))
-		var/mob/living/carbon/C = M
-		C.losebreath += 2
-	if(prob(20))
-		M.emote("gasp")
+		C = M
+		CHECK_DNA_AND_SPECIES(C)
+		if(NOBREATH in C.dna.species.specflags)
+			. = FALSE
+
+	if(.)
+		M.adjustOxyLoss(5, 0)
+		if(C)
+			C.losebreath += 2
+		if(prob(20))
+			M.emote("gasp")
 	..()
-	. = 1
 
 /datum/reagent/toxin/slimejelly
 	name = "Slime Jelly"