diff --git a/lib/goby/entity/entity.rb b/lib/goby/entity/entity.rb
index 9c37f57..4d1b3c1 100644
--- a/lib/goby/entity/entity.rb
+++ b/lib/goby/entity/entity.rb
@@ -13,13 +13,18 @@ class Entity
 
     # @param [String] name the name.
     # @param [Hash] stats hash of stats
+    # @option stats [Integer] :max_hp maximum health points. Set to be positive.
+    # @option stats [Integer] :hp current health points. Set to be nonnegative.
+    # @option stats [Integer] :attack strength in battle. Set to be positive.
+    # @option stats [Integer] :defense protection from attacks. Set to be positive.
+    # @option stats [Integer] :agility speed of commands in battle. Set to be positive.
     # @param [[Couple(Item, Integer)]] inventory a list of pairs of items and their respective amounts.
     # @param [Integer] gold the currency used for economical transactions.
     # @param [[BattleCommand]] battle_commands the commands that can be used in battle.
     # @param [Hash] outfit the collection of equippable items currently worn.
     def initialize(name: "Entity", stats: {}, inventory: [], gold: 0, battle_commands: [], outfit: {})
       @name = name
-      @stats = set_stats(stats)
+      set_stats(stats)
       @inventory = inventory
       set_gold(gold)
 
@@ -266,6 +271,43 @@ def set_gold(gold)
       check_and_set_gold
     end
 
+    # Sets stats
+    #
+    # @param [Hash] passed_in_stats value pairs of stats
+    # @option passed_in_stats [Integer] :max_hp maximum health points. Set to be positive.
+    # @option passed_in_stats [Integer] :hp current health points. Set to be nonnegative.
+    # @option passed_in_stats [Integer] :attack strength in battle. Set to be positive.
+    # @option passed_in_stats [Integer] :defense protection from attacks. Set to be positive.
+    # @option passed_in_stats [Integer] :agility speed of commands in battle. Set to be positive.
+    def set_stats(passed_in_stats)
+      current_stats = @stats || { max_hp: 1, hp: nil, attack: 1, defense: 1, agility: 1 }
+      constructed_stats = current_stats.merge(passed_in_stats)
+
+      # Set hp to max_hp if hp not specified
+      constructed_stats[:hp] = constructed_stats[:hp] || constructed_stats[:max_hp]
+      # hp should not be greater than max_hp
+      constructed_stats[:hp] = [constructed_stats[:hp], constructed_stats[:max_hp]].min
+      #ensure hp is at least 0
+      constructed_stats[:hp] = constructed_stats[:hp] > 0 ? constructed_stats[:hp] : 0
+      #ensure all other stats > 0
+      constructed_stats.each do |key,value|
+        if [:max_hp, :attack, :defense, :agility].include?(key)
+          constructed_stats[key] = value.nonpositive? ? 1 : value
+        end
+      end
+
+      @stats = constructed_stats
+    end
+
+    # getter for stats
+    #
+    # @return [Object]
+    def stats
+      # attr_reader makes sure stats cannot be set via stats=
+      # freeze makes sure that stats []= cannot be used
+      @stats.freeze
+    end
+
     # Unequips the specified item from the entity's outfit.
     #
     # @param [Item, String] item the item (or its name) to unequip.
@@ -302,38 +344,6 @@ def ==(rhs)
       @name == rhs.name
     end
 
-    # Sets stats
-    #
-    # @param [Hash] passed_in_stats value pairs of stats
-    def set_stats(passed_in_stats)
-      current_stats = @stats || { max_hp: 1, hp: nil, attack: 1, defense: 1, agility: 1 }
-      constructed_stats = current_stats.merge(passed_in_stats)
-
-      # Set hp to max_hp if hp not specified
-      constructed_stats[:hp] = constructed_stats[:hp] || constructed_stats[:max_hp]
-      # hp should not be greater than max_hp
-      constructed_stats[:hp] = [constructed_stats[:hp], constructed_stats[:max_hp]].min
-      #ensure hp is at least 0
-      constructed_stats[:hp] = constructed_stats[:hp] > 0 ? constructed_stats[:hp] : 0
-      #ensure all other stats > 0
-      constructed_stats.each do |key,value|
-        if [:max_hp, :attack, :defense, :agility].include?(key)
-          constructed_stats[key] = value.negative? ? 1 : value
-        end
-      end
-
-      @stats = constructed_stats
-    end
-
-    # getter for stats
-    #
-    # @return [Object]
-    def stats
-      # attr_reader makes sure stats cannot be set via stats=
-      # freeze makes sure that stats []= cannot be used
-      @stats.freeze
-    end
-
     attr_accessor :name
 
     attr_accessor :inventory
diff --git a/lib/goby/item/equippable.rb b/lib/goby/item/equippable.rb
index fbae7e3..8dda44f 100644
--- a/lib/goby/item/equippable.rb
+++ b/lib/goby/item/equippable.rb
@@ -25,12 +25,8 @@ def type
     def alter_stats(entity, equipping)
       stats_to_change = entity.stats.dup
       affected_stats = [:attack, :defense, :agility, :max_hp]
-      if equipping
-        operator = :+
-      else
-        operator = :-
-      end
 
+      operator = equipping ? :+ : :-
       affected_stats.each do |stat|
         stats_to_change[stat]= stats_to_change[stat].send(operator, stat_change[stat]) if stat_change[stat]
       end
diff --git a/spec/goby/entity/entity_spec.rb b/spec/goby/entity/entity_spec.rb
index 09b7f0f..d66a43c 100644
--- a/spec/goby/entity/entity_spec.rb
+++ b/spec/goby/entity/entity_spec.rb
@@ -617,12 +617,12 @@
     end
 
     it "only changes specified stats" do
-      entity = Entity.new(stats: { max_hp: 2, hp: 2, attack: 1, defense: 4, agility: 4 })
+      entity = Entity.new(stats: { max_hp: 4, hp: 2, attack: 1, defense: 4, agility: 4 })
 
-      entity.set_stats({ attack: 2 })
+      entity.set_stats({ max_hp: 3, attack: 2 })
 
       stats = entity.stats
-      expect(stats[:max_hp]).to eq 2
+      expect(stats[:max_hp]).to eq 3
       expect(stats[:hp]).to eq 2
       expect(stats[:attack]).to eq 2
       expect(stats[:defense]).to eq 4
@@ -650,9 +650,9 @@
     end
 
     it "non hp values cannot go below 1" do
-      entity = Entity.new(stats: { max_hp: 2, attack: 1, defense: 1, agility: 1 })
+      entity = Entity.new(stats: { max_hp: 2, attack: 3, defense: 2, agility: 3 })
 
-      entity.set_stats({ max_hp: -1, hp: -1, attack: -1, defense: -1, agility: -1 })
+      entity.set_stats({ max_hp: 0, attack: 0, defense: 0, agility: 0 })
 
       stats = entity.stats
       expect(stats[:max_hp]).to eq 1