Refactor Ugin's Conjurant, Protean Hydra with a new ability. Fixed Ashiok, Dream Renderer (#5737)

* Refactor Ugin's Conjurant, Protean Hydra with a new ability

* pushing bugfix for Ashiok, Dream Renderer not milling correctly.

Mage/src/main/java/mage/abilities/effects/PreventDamageAndRemoveCountersEffect.java

@@ -0,0 +1,60 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package mage.abilities.effects;
+
+import mage.abilities.Ability;
+import mage.constants.Duration;
+import mage.counters.CounterType;
+import mage.game.Game;
+import mage.game.events.GameEvent;
+import mage.game.permanent.Permanent;
+
+/**
+ *
+ * @author antoni-g
+ */
+public class PreventDamageAndRemoveCountersEffect extends PreventionEffectImpl {
+
+    public PreventDamageAndRemoveCountersEffect() {
+        super(Duration.WhileOnBattlefield, Integer.MAX_VALUE, false, false);
+        staticText = "If damage would be dealt to {this}, prevent that damage and remove that many +1/+1 counters from it";
+    }
+
+    public PreventDamageAndRemoveCountersEffect(final PreventDamageAndRemoveCountersEffect effect) {
+        super(effect);
+    }
+
+    @Override
+    public PreventDamageAndRemoveCountersEffect copy() {
+        return new PreventDamageAndRemoveCountersEffect(this);
+    }
+
+    @Override
+    public boolean apply(Game game, Ability source) {
+        return true;
+    }
+
+    @Override
+    public boolean replaceEvent(GameEvent event, Ability source, Game game) {
+        int damage = event.getAmount();
+        preventDamageAction(event, source, game);
+        Permanent permanent = game.getPermanent(source.getSourceId());
+        if (permanent != null) {
+            permanent.removeCounters(CounterType.P1P1.createInstance(damage), game); //MTG ruling (this) loses counters even if the damage isn't prevented
+        }
+        return false;
+    }
+
+    @Override
+    public boolean applies(GameEvent event, Ability source, Game game) {
+        if (super.applies(event, source, game)) {
+            if (event.getTargetId().equals(source.getSourceId())) {
+                return true;
+            }
+        }
+        return false;
+    }
+}