diff --git a/Piece.cpp b/Piece.cpp
index f15180a..251e5e9 100644
--- a/Piece.cpp
+++ b/Piece.cpp
@@ -126,10 +126,9 @@ std::vector<Move> King::getLegalMoves(const Square &from, const Board &board) co
     // will this actually work?
     moveList.erase(
             std::remove_if(moveList.begin(), moveList.end(),
-                           [&](const Square &x) {
-                               return std::find(x.begin(), x.end(), !x.isValid()) != x.end();
-                           }),
-                           moveList.end());
+                           [&](const auto &x) {
+                               return !x.to.isValid();
+                           }));
     return moveList;
 }
 
diff --git a/Piece.hpp b/Piece.hpp
index 8d407c8..7f24412 100644
--- a/Piece.hpp
+++ b/Piece.hpp
@@ -11,6 +11,7 @@
 #pragma once
 
 #include <cstdint>
+#include <algorithm>
 #include <utility>
 #include <string>
 #include <memory>
@@ -34,6 +35,10 @@ enum File {
     A = 0, B = 1, C = 2, D = 3, E = 4, F = 5, G = 6, H = 7, INVALID_FILE = 255
 };
 
+enum CastleSide {
+    KINGSIDE = 1, QUEENSIDE = 2
+};
+
 struct Square {
     Rank rank;
     File file;
@@ -101,11 +106,18 @@ class King : public Piece {
         return inCheck;
     }
 
-    bool checkForCastle() const {
-        return canCastle;
+    bool checkForCastle(enum CastleSide side) const {
+        if(side == KINGSIDE) {
+            return canCastleKS;
+        } else if(side == QUEENSIDE) {
+            return canCastleQS;
+        } else {
+            return false;
+        }
     }
   protected:
-    bool canCastle = true;
+    bool canCastleQS = true;
+    bool canCastleKS = true;
     bool inCheck = false;
 };