diff --git a/system/libs/pot/OTS_MonstersList.php b/system/libs/pot/OTS_MonstersList.php
index bdc6bd06..fb51a085 100644
--- a/system/libs/pot/OTS_MonstersList.php
+++ b/system/libs/pot/OTS_MonstersList.php
@@ -174,6 +174,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
  * @return OTS_Monster Monster.
  * @throws DOMException On DOM operation error.
  */
+	#[\ReturnTypeWillChange]
     public function current()
     {
         return $this->getMonster( key($this->monsters) );
@@ -187,7 +188,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
 /**
  * Moves to next iterator monster.
  */
-    public function next()
+    public function next(): void
     {
         next($this->monsters);
     }
@@ -197,6 +198,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
  *
  * @return string Current position key.
  */
+	#[\ReturnTypeWillChange]
     public function key()
     {
         return key($this->monsters);
@@ -207,7 +209,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
  *
  * @return bool If iterator has anything more.
  */
-    public function valid()
+    public function valid(): bool
     {
         return key($this->monsters) !== null;
     }
@@ -215,7 +217,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
 /**
  * Resets iterator index.
  */
-    public function rewind()
+    public function rewind(): void
     {
         reset($this->monsters);
     }
@@ -226,6 +228,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
  * @param string $offset Array key.
  * @return bool True if it's set.
  */
+	#[\ReturnTypeWillChange]
     public function offsetExists($offset)
     {
         return isset($this->monsters[$offset]);
@@ -239,6 +242,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
  * @return OTS_Monster Monster instance.
  * @throws DOMException On DOM operation error.
  */
+	#[\ReturnTypeWillChange]
     public function offsetGet($offset)
     {
         return $this->getMonster($offset);
@@ -251,6 +255,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
  * @param mixed $value Field value.
  * @throws E_OTS_ReadOnly Always - this class is read-only.
  */
+	#[\ReturnTypeWillChange]
     public function offsetSet($offset, $value)
     {
         throw new E_OTS_ReadOnly();
@@ -262,6 +267,7 @@ class OTS_MonstersList implements Iterator, Countable, ArrayAccess
  * @param string|int $offset Array key.
  * @throws E_OTS_ReadOnly Always - this class is read-only.
  */
+	#[\ReturnTypeWillChange]
     public function offsetUnset($offset)
     {
         throw new E_OTS_ReadOnly();
diff --git a/system/libs/pot/OTS_SpellsList.php b/system/libs/pot/OTS_SpellsList.php
index 8455b7f2..21b80ef4 100644
--- a/system/libs/pot/OTS_SpellsList.php
+++ b/system/libs/pot/OTS_SpellsList.php
@@ -308,7 +308,7 @@ class OTS_SpellsList implements IteratorAggregate, Countable
  * @since 0.1.5
  * @return AppendIterator Iterator for all spells.
  */
-    public function getIterator()
+    public function getIterator(): Traversable
     {
         $iterator = new AppendIterator();
         $iterator->append( new ArrayIterator($this->runes) );