So when I add Mv core or any Mv to my 1.8.8 server i keep getting this issue

_15.07 07:52:30 [Server] ERROR Error occurred while enabling Multiverse-Core v4.1.0-b775 (Is it up to date?)
15.07 07:52:30 [Server] INFO java.lang.NoClassDefFoundError: org/bukkit/entity/Phantom
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.utils.SimpleWorldPurger.killDecision(SimpleWorldPurger.java:152) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.utils.SimpleWorldPurger.purgeWorld(SimpleWorldPurger.java:119) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.utils.SimpleWorldPurger.purgeWorld(SimpleWorldPurger.java:197) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.utils.SimpleWorldPurger.purgeWorld(SimpleWorldPurger.java:74) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.MVWorld$SpawningPropertyValidator.validateChange(MVWorld.java:286) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.MVWorld$SpawningPropertyValidator.validateChange(MVWorld.java:260) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.serializationconfig.SerializationConfig.SerializationConfig.validate(SerializationConfig.java:893) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.serializationconfig.SerializationConfig.SerializationConfig.setPropertyValue(SerializationConfig.java:443) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.serializationconfig.SerializationConfig.SerializationConfig.setPropertyValue(SerializationConfig.java:368) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.serializationconfig.SerializationConfig.SerializationConfig.setPropertyValue(SerializationConfig.java:353) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.serializationconfig.SerializationConfig.SerializationConfig.setPropertyValueUnchecked(SerializationConfig.java:736) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.WorldProperties.setAllowAnimalSpawn(WorldProperties.java:424) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.MVWorld.setAllowAnimalSpawn(MVWorld.java:767) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.MVWorld.validateEntitySpawns(MVWorld.java:195) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.MVWorld.validateProperties(MVWorld.java:205) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.MVWorld.(MVWorld.java:94) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.MVWorld.(MVWorld.java:59) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.utils.WorldManager.doLoad(WorldManager.java:477) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.utils.WorldManager.doLoad(WorldManager.java:448) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.utils.WorldManager.doLoad(WorldManager.java:423) ~[?:?]
15.07 07:52:30 [Server] INFO at com.onarandombox.MultiverseCore.utils.WorldManager.loadWorlds(WorldManager.java:728) ~_

I have downloaded the latest file for all of the mv plugins and it still gives this issue

For 1.8.x, you will need to use an older version of Multiverse for it to work. Multiverse 2.5 should work: https://dev.bukkit.org/projects/multiverse-core/files/898527

The version of MV I linked above should solve your issue, I will close it for now. If you still face any issue, feel free to reopen the issue or come to our MV discord https://discord.gg/NZtfKky