[SPM] Implement Marvel's Spider-Man

Mage/src/main/java/mage/abilities/effects/common/DrawCardsEqualToDifferenceEffect.java

@@ -0,0 +1,37 @@
+package mage.abilities.effects.common;
+
+import mage.abilities.Ability;
+import mage.abilities.effects.OneShotEffect;
+import mage.constants.Outcome;
+import mage.game.Game;
+import mage.players.Player;
+
+/**
+ * @author TheElk801
+ */
+public class DrawCardsEqualToDifferenceEffect extends OneShotEffect {
+
+    private final int amount;
+
+    public DrawCardsEqualToDifferenceEffect(int amount) {
+        super(Outcome.Benefit);
+        this.amount = amount;
+        staticText = "draw cards equal to the difference";
+    }
+
+    private DrawCardsEqualToDifferenceEffect(final DrawCardsEqualToDifferenceEffect effect) {
+        super(effect);
+        this.amount = effect.amount;
+    }
+
+    @Override
+    public DrawCardsEqualToDifferenceEffect copy() {
+        return new DrawCardsEqualToDifferenceEffect(this);
+    }
+
+    @Override
+    public boolean apply(Game game, Ability source) {
+        Player player = game.getPlayer(source.getControllerId());
+        return player != null && player.drawCards(Math.max(amount - player.getHand().size(), 0), source, game) > 0;
+    }
+}