replace groovy code with ability in card script

release/Magarena/scripts/Centaur_s_Herald.groovy

@@ -1,28 +0,0 @@
-[
-    new MagicPermanentActivation(
-        new MagicActivationHints(MagicTiming.Flash),
-        "Token"
-    ) {
-
-        @Override
-        public Iterable<MagicEvent> getCostEvent(final MagicPermanent source) {
-            return [
-                new MagicPayManaCostSacrificeEvent(source, "{2}{G}")
-            ];
-        }
-
-        @Override
-        public MagicEvent getPermanentEvent(final MagicPermanent source, final MagicPayedCost payedCost) {
-            return new MagicEvent(
-                source,
-                this,
-                "Put a 3/3 green Centaur creature token onto the battlefield."
-            );
-        }
-
-        @Override
-        public void executeEvent(final MagicGame game, final MagicEvent event) {
-            game.doAction(new MagicPlayTokenAction(event.getPlayer(), TokenCardDefinitions.get("Centaur3")));
-        }
-    }
-]

release/Magarena/scripts/Centaur_s_Herald.txt

@@ -7,5 +7,5 @@ type=Creature
 subtype=Elf,Scout
 cost={G}
 pt=0/1
+ability=pay {2}{G}, {S}: PN puts a 3/3 green Centaur creature token onto the battlefield.
 timing=main
-requires_groovy_code