diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/boiler/trapper.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/boiler/trapper.dm
index c18973209220..e6c8061bd0fe 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/boiler/trapper.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/boiler/trapper.dm
@@ -20,7 +20,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/boiler_trapper
 
 /datum/xeno_strain/trapper/apply_strain(mob/living/carbon/xenomorph/boiler/boiler)
-	. = ..()
 	if(!istype(boiler))
 		return FALSE
 
@@ -35,7 +34,6 @@
 
 	boiler.speed_modifier += XENO_SPEED_SLOWMOD_TIER_5 // compensating for base buffs
 	boiler.recalculate_everything()
-	return TRUE
 
 /datum/behavior_delegate/boiler_trapper
 	name = "Boiler Trapper Behavior Delegate"
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/carrier/eggsac.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/carrier/eggsac.dm
index f1ba672d63e5..97d6770be33c 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/carrier/eggsac.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/carrier/eggsac.dm
@@ -17,7 +17,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/carrier_eggsac
 
 /datum/xeno_strain/eggsac/apply_strain(mob/living/carbon/xenomorph/carrier/carrier)
-	. = ..()
 
 	carrier.plasma_types = list(PLASMA_EGG)
 	carrier.phero_modifier += XENO_PHERO_MOD_LARGE // praetorian level pheremones
@@ -32,7 +31,6 @@
 	carrier.eggs_max = 12
 	carrier.egg_planting_range = 2
 	carrier.update_eggsac_overlays()
-	return TRUE
 
 #define EGGSAC_OFF_WEED_EGGCAP 4
 #define EGGSAC_EGG_SUSTAIN_DISTANCE 14
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/crusher/charger.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/crusher/charger.dm
index f2dd564cb2ee..84877b43571e 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/crusher/charger.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/crusher/charger.dm
@@ -32,8 +32,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/crusher_charger
 
 /datum/xeno_strain/charger/apply_strain(mob/living/carbon/xenomorph/crusher/crusher)
-	. = ..()
-
 	crusher.small_explosives_stun = FALSE
 	crusher.health_modifier += XENO_HEALTH_MOD_LARGE
 	crusher.speed_modifier += XENO_SPEED_FASTMOD_TIER_3
@@ -42,7 +40,6 @@
 	crusher.ignore_aura = "frenzy" // no funny crushers going 7 morbillion kilometers per second
 	crusher.phero_modifier = -crusher.caste.aura_strength
 	crusher.recalculate_everything()
-	return TRUE
 
 /datum/behavior_delegate/crusher_charger
 	name = "Charger Crusher Behavior Delegate"
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/defender/steel_crest.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/defender/steel_crest.dm
index 891c1ce08e1e..1560387c218b 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/defender/steel_crest.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/defender/steel_crest.dm
@@ -18,8 +18,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/defender_steel_crest
 
 /datum/xeno_strain/steel_crest/apply_strain(mob/living/carbon/xenomorph/defender/defender)
-	. = ..()
-
 	defender.damage_modifier -= XENO_DAMAGE_MOD_VERY_SMALL
 	if(defender.fortify)
 		defender.ability_speed_modifier += 2.5
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/drone/gardener.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/drone/gardener.dm
index 456768cdd25a..88a6cb50148b 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/drone/gardener.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/drone/gardener.dm
@@ -19,8 +19,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/drone_gardener
 
 /datum/xeno_strain/gardener/apply_strain(mob/living/carbon/xenomorph/drone/drone)
-	. = ..()
-
 	drone.available_fruits = list(
 		/obj/effect/alien/resin/fruit/greater,
 		/obj/effect/alien/resin/fruit/unstable,
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/drone/healer.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/drone/healer.dm
index bca247899428..6a985eb8d7ec 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/drone/healer.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/drone/healer.dm
@@ -22,8 +22,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/drone_healer
 
 /datum/xeno_strain/healer/apply_strain(mob/living/carbon/xenomorph/drone/drone)
-	. = ..()
-
 	drone.phero_modifier += XENO_PHERO_MOD_LARGE
 	drone.plasma_types += PLASMA_PHEROMONE
 	drone.damage_modifier -= XENO_DAMAGE_MOD_VERY_SMALL
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/facehugger/watcher.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/facehugger/watcher.dm
index c5d9986c7b6a..7fba30b6f352 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/facehugger/watcher.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/facehugger/watcher.dm
@@ -13,11 +13,8 @@
 	behavior_delegate_type = /datum/behavior_delegate/facehugger_watcher
 
 /datum/xeno_strain/watcher/apply_strain(mob/living/carbon/xenomorph/facehugger/huggy)
-	. = ..()
-
 	huggy.viewsize = 10
 	huggy.layer = initial(huggy.layer)
-	return TRUE
 
 // This has no special effects, it's just here to skip `/datum/behavior_delegate/facehugger_base/on_life()`.
 /datum/behavior_delegate/facehugger_watcher
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/hivelord/resin_whisperer.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/hivelord/resin_whisperer.dm
index 2b3e790ab21b..cca2210a30b4 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/hivelord/resin_whisperer.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/hivelord/resin_whisperer.dm
@@ -17,8 +17,6 @@
 	)
 
 /datum/xeno_strain/resin_whisperer/apply_strain(mob/living/carbon/xenomorph/hivelord/hivelord)
-	. = ..()
-
 	hivelord.plasmapool_modifier = 0.8 // -20% plasma pool
 	hivelord.extra_build_dist = 12 // 1 + 12 = 13 tile build range
 	hivelord.can_stack_builds = TRUE
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/lurker/vampire.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/lurker/vampire.dm
index 4beec851c420..1f220a02dd79 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/lurker/vampire.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/lurker/vampire.dm
@@ -16,8 +16,6 @@
 	)
 
 /datum/xeno_strain/vampire/apply_strain(mob/living/carbon/xenomorph/lurker/lurker)
-	. = ..()
-
 	lurker.plasmapool_modifier = 0
 	lurker.health_modifier -= XENO_HEALTH_MOD_MED
 	lurker.speed_modifier += XENO_SPEED_FASTMOD_TIER_1
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/dancer.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/dancer.dm
index 2d6d7bb7b15d..ef2eb377d01e 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/dancer.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/dancer.dm
@@ -20,8 +20,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/praetorian_dancer
 
 /datum/xeno_strain/dancer/apply_strain(mob/living/carbon/xenomorph/praetorian/prae)
-	. = ..()
-
 	prae.armor_modifier -= XENO_ARMOR_MOD_VERY_SMALL
 	prae.speed_modifier += XENO_SPEED_FASTMOD_TIER_5
 	prae.plasma_types = list(PLASMA_CATECHOLAMINE)
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/oppressor.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/oppressor.dm
index 6d3d50c1d12d..74dc1b9d6ecd 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/oppressor.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/oppressor.dm
@@ -23,8 +23,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/oppressor_praetorian
 
 /datum/xeno_strain/oppressor/apply_strain(mob/living/carbon/xenomorph/praetorian/prae)
-	. = ..()
-
 	prae.damage_modifier -= XENO_DAMAGE_MOD_SMALL
 	prae.explosivearmor_modifier += XENO_EXPOSIVEARMOR_MOD_SMALL
 	prae.small_explosives_stun = FALSE
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/vanguard.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/vanguard.dm
index b8baef5e518f..a5d4b757cf6d 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/vanguard.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/vanguard.dm
@@ -21,8 +21,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/praetorian_vanguard
 
 /datum/xeno_strain/vanguard/apply_strain(mob/living/carbon/xenomorph/praetorian/prae)
-	. = ..()
-
 	prae.speed_modifier += XENO_SPEED_FASTMOD_TIER_3
 	prae.health_modifier -= XENO_HEALTH_MOD_MED
 	prae.claw_type = CLAW_TYPE_SHARP
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/warden.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/warden.dm
index 3cb42e59e175..56dfca99a732 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/warden.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/praetorian/warden.dm
@@ -21,8 +21,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/praetorian_warden
 
 /datum/xeno_strain/warden/apply_strain(mob/living/carbon/xenomorph/praetorian/prae)
-	. = ..()
-
 	// Make a 'halftank'
 	prae.speed_modifier += XENO_SPEED_SLOWMOD_TIER_5
 	prae.damage_modifier -= XENO_DAMAGE_MOD_SMALL
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/ravager/berserker.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/ravager/berserker.dm
index 80261d295ab6..7b912cc620a0 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/ravager/berserker.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/ravager/berserker.dm
@@ -17,8 +17,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/ravager_berserker
 
 /datum/xeno_strain/berserker/apply_strain(mob/living/carbon/xenomorph/ravager/ravager)
-	. = ..()
-
 	ravager.plasma_max = 0
 	ravager.health_modifier -= XENO_HEALTH_MOD_MED
 	ravager.armor_modifier += XENO_ARMOR_MOD_VERY_SMALL
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/ravager/hedgehog.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/ravager/hedgehog.dm
index 75a85ca3e72e..4e452fb1a18a 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/ravager/hedgehog.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/ravager/hedgehog.dm
@@ -17,8 +17,6 @@
 	behavior_delegate_type = /datum/behavior_delegate/ravager_hedgehog
 
 /datum/xeno_strain/hedgehog/apply_strain(mob/living/carbon/xenomorph/ravager/ravager)
-	. = ..()
-
 	ravager.plasma_max = 0
 	ravager.small_explosives_stun = FALSE
 	ravager.explosivearmor_modifier += XENO_EXPOSIVEARMOR_MOD_SMALL
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/castes/runner/acid.dm b/code/modules/mob/living/carbon/xenomorph/strains/castes/runner/acid.dm
index d768ad61ce2d..8f2ce0ef7150 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/castes/runner/acid.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/castes/runner/acid.dm
@@ -17,15 +17,12 @@
 	behavior_delegate_type = /datum/behavior_delegate/runner_acider
 
 /datum/xeno_strain/acider/apply_strain(mob/living/carbon/xenomorph/runner/runner)
-	. = ..()
-
 	runner.speed_modifier += XENO_SPEED_SLOWMOD_TIER_5
 	runner.armor_modifier += XENO_ARMOR_MOD_MED
 	runner.health_modifier += XENO_HEALTH_MOD_ACIDER
 
 	runner.recalculate_everything()
 
-
 /datum/behavior_delegate/runner_acider
 	var/acid_amount = 0
 
diff --git a/code/modules/mob/living/carbon/xenomorph/strains/xeno_strain.dm b/code/modules/mob/living/carbon/xenomorph/strains/xeno_strain.dm
index 0098f61b1e29..586bf95aec7b 100644
--- a/code/modules/mob/living/carbon/xenomorph/strains/xeno_strain.dm
+++ b/code/modules/mob/living/carbon/xenomorph/strains/xeno_strain.dm
@@ -21,11 +21,11 @@
  *
  * Returns a bool indicating if the strain was successfully applied.
  */
-/datum/xeno_strain/proc/apply_strain(mob/living/carbon/xenomorph/xeno)
-	SHOULD_CALL_PARENT(TRUE)
+/datum/xeno_strain/proc/_add_to_xeno(mob/living/carbon/xenomorph/xeno)
+	// Override `apply_changes()`, not this! (Unless you know what you're doing.)
+	SHOULD_NOT_OVERRIDE(TRUE)
 
 	xeno.strain = src
-	register_signals(xeno)
 
 	// Update the xeno's actions.
 	for(var/action_path in actions_to_remove)
@@ -41,17 +41,24 @@
 		xeno.behavior_delegate.bound_xeno = xeno
 		xeno.behavior_delegate.add_to_xeno()
 
+	apply_strain()
+
 	xeno.update_icons()
 	xeno.hive.hive_ui.update_xeno_info()
 
-	// Give them all the info about the strain.
+	// Give them all of the info about the strain.
 	to_chat(xeno, SPAN_XENOANNOUNCE(description))
 	if(flavor_description)
 		to_chat(xeno, SPAN_XENOLEADER(flavor_description))
 	return TRUE
 
-/// TODO: documentation
-/datum/xeno_strain/proc/register_signals(mob/living/carbon/xenomorph/xeno)
+/**
+ * Adds any special modifiers/changes from this strain to `xeno`.
+ *
+ * Called when the strain is first added to the player.
+ */
+/datum/xeno_strain/proc/apply_strain(mob/living/carbon/xenomorph/xeno)
+	// Override with custom behaviour.
 	return
 
 
@@ -85,7 +92,7 @@
 
 	// Create the strain datum and apply it to the xeno.
 	var/datum/xeno_strain/strain_instance = new chosen_strain()
-	if(strain_instance.apply_strain(src))
+	if(strain_instance._add_to_xeno(src))
 		xeno_jitter(1.5 SECONDS)
 		// If it applied successfully, add it to the logs.
 		log_strain("[name] purchased strain '[strain_instance.type]'")