diff --git a/BaseClasses.py b/BaseClasses.py
index f0b4e184..912f9957 100644
--- a/BaseClasses.py
+++ b/BaseClasses.py
@@ -368,6 +368,19 @@ class CollectionState(object):
     def bottle_count(self):
         return len([pritem for pritem in self.prog_items if pritem.startswith('Bottle')])
 
+    def has_hearts(self, count):
+        # Warning: This oncly considers items that are marked as advancement items
+        return self.heart_count() >= count
+
+    def heart_count(self):
+        # Warning: This oncly considers items that are marked as advancement items
+        return (
+            self.item_count('Boss Heart Container')
+            + self.item_count('Sanctuary Heart Container')
+            + self.item_count('Piece of Heart') // 4
+            + 3 # starting hearts
+        )
+
     def can_lift_heavy_rocks(self):
         return self.has('Titans Mitts')
 
diff --git a/ItemList.py b/ItemList.py
index 877d332e..d2847613 100644
--- a/ItemList.py
+++ b/ItemList.py
@@ -228,6 +228,16 @@ def generate_itempool(world):
     if world.keysanity:
         world.itempool.extend(get_dungeon_item_pool(world))
 
+    # logic has some branches where having 4 hearts is one possible requirement (of several alternatives)
+    # rather than making all hearts/heart pieces progression items (which slows down generation considerably)
+    # We mark one random heart container as an advancement item (or 4 heart peices in expert mode)
+    if world.difficulty in ['easy', 'normal', 'hard']:
+        [item for item in world.itempool if item.name == 'Boss Heart Container'][0].advancement = True
+    elif world.difficulty in ['expert']:
+        adv_heart_pieces = [item for item in world.itempool if item.name == 'Piece of Heart'][0:4]
+        for hp in adv_heart_pieces:
+            hp.advancement = True
+
     # shuffle medallions
     mm_medallion = ['Ether', 'Quake', 'Bombos'][random.randint(0, 2)]
     tr_medallion = ['Ether', 'Quake', 'Bombos'][random.randint(0, 2)]
diff --git a/Rules.py b/Rules.py
index 5f4a26ac..80f3dba9 100644
--- a/Rules.py
+++ b/Rules.py
@@ -185,9 +185,17 @@ def global_rules(world):
     set_rule(world.get_entrance('Fairy Ascension Mirror Spot'), lambda state: state.has_Mirror() and state.has_Pearl())  # need to lift flowers
     set_rule(world.get_entrance('Isolated Ledge Mirror Spot'), lambda state: state.has_Mirror())
     set_rule(world.get_entrance('Superbunny Cave Exit (Bottom)'), lambda state: False)  # Cannot get to bottom exit from top. Just exists for shuffling
-    set_rule(world.get_location('Spike Cave'), lambda state: state.has('Hammer') and state.can_lift_rocks() and (state.has('Cane of Byrna') or state.has('Cape')) and state.can_extend_magic())
-    # TODO: Current-VT logic is: hammer and lift_rocks and ((cape and extend) or (byrna and (can-take-damage OR canextend)))
-    # Is that really good enough? Can you really get through with byrna, single magic w/o refills and only 3 hearts? (answer: probably but seems to requires tas-like timing.)
+    set_rule(world.get_location('Spike Cave'), lambda state:
+             state.has('Hammer') and state.can_lift_rocks()
+             and ((state.has('Cape') and state.can_extend_magic())
+                  or (state.has('Cane of Byrna') and state.can_extend_magic())
+                  or (state.world.can_take_damage
+                      and state.has('Cane of Byrna')
+                      and (state.has_Boots() or state.has_hearts(4))
+                     )
+                 )
+            )
+
     set_rule(world.get_location('Hookshot Cave - Top Right'), lambda state: state.has('Hookshot'))
     set_rule(world.get_location('Hookshot Cave - Top Left'), lambda state: state.has('Hookshot'))
     set_rule(world.get_location('Hookshot Cave - Bottom Right'), lambda state: state.has('Hookshot') or state.has('Pegasus Boots'))
@@ -271,7 +279,7 @@ def global_rules(world):
 
     set_rule(world.get_entrance('Misery Mire Entrance Gap'), lambda state: (state.has_Boots() or state.has('Hookshot')) and (state.has_sword() or state.has('Fire Rod') or state.has('Ice Rod') or state.has('Hammer') or state.has('Cane of Somaria') or state.has('Bow')))  # need to defeat wizzrobes, bombs don't work ...
     set_rule(world.get_location('Misery Mire - Big Chest'), lambda state: state.has('Big Key (Misery Mire)'))
-    set_rule(world.get_location('Misery Mire - Spike Chest'), lambda state: state.world.can_take_damage or state.has('Cane of Byrna') or state.has('Cape'))
+    set_rule(world.get_location('Misery Mire - Spike Chest'), lambda state: (state.world.can_take_damage and state.has_hearts(4)) or state.has('Cane of Byrna') or state.has('Cape'))
     set_rule(world.get_entrance('Misery Mire Big Key Door'), lambda state: state.has('Big Key (Misery Mire)'))
     # you can squander the free small key from the pot by opening the south door to the north west switch room, locking you out of accessing a color switch ...
     # big key gives backdoor access to that from the teleporter in the north west