Minecraft wiki entry for Ender_Dragon, associated text: When a re-summoned Ender dragon is slain, the same events occur except that only 500 experience points are dropped ‌[Java Edition only] and no more than 20 gateway portals are generated. The dragon egg appears the first time the Ender dragon is slain in Java Edition, and the first and second time in Bedrock edition; it does not appear after any following dragon slaying.