Help needed : Pixelmon server won't start with spongeforge

Hi, I’m a new server owner trying to make a small pixelmon server. My only issue is that spongeforge doesn’t seem to work. I have pixelmon installed on my server however when I place the spongeforge jar in my mods folder the server does not start. Here are some logs if somebody could help me and tell me what I can do that’d be great.

> [16:53:35] [Server thread/INFO]: Starting minecraft server version 1.8.9
> [16:53:53] [Server thread/INFO]: Loading properties
> [16:53:53] [Server thread/INFO]: Default game type: SURVIVAL
> [16:53:53] [Server thread/INFO]: Generating keypair
> [16:53:53] [Server thread/INFO]: Starting Minecraft server on
> [16:53:53] [Server thread/INFO]: Using epoll channel type
> [16:53:59] [Server thread/INFO]: Preparing level "New"
> [16:54:00] [Server thread/INFO]: Preparing start region for level 0
> [16:54:01] [Server thread/INFO]: Preparing spawn area: 17%
> [16:54:02] [Server thread/INFO]: Preparing spawn area: 39%
> [16:54:03] [Server thread/INFO]: Done (3.407s)! For help, type "help" or "?"
> [16:56:52] [User Authenticator #1/INFO]: UUID of player DoggyFroggyFoggy is 309c361b-1df5-4664-b1ee-4ef77bc351a1
> [16:56:53] [Server thread/INFO]: DoggyFroggyFoggy lost connection: TextComponent{text='Mod rejections [FMLMod:pixelmon{4.2.5}]', siblings=[], style=Style{hasParent=false, color=null, bold=null, italic=null, underlined=null, obfuscated=null, clickEvent=null, hoverEvent=null, insertion=null}}
> [16:56:53] [Server thread/INFO]: DoggyFroggyFoggy left the game
> [16:57:47] [Server thread/INFO]: [Server] Server shutdown in 10 seconds! Saving..
> [16:57:47] [Server thread/INFO]: Saving...
> [16:57:47] [Server thread/INFO]: Saved the world
> [16:57:57] [Server thread/INFO]: Stopping the server
> [16:57:57] [Server thread/INFO]: Stopping server
> [16:57:57] [Server thread/INFO]: Saving players
> [16:57:57] [Server thread/INFO]: Saving worlds
> [16:57:57] [Server thread/INFO]: Saving chunks for level 'New'/Overworld
> [16:57:57] [Server thread/INFO]: Saving chunks for level 'New'/Nether
> [16:57:57] [Server thread/INFO]: Saving chunks for level 'New'/The End

If there’s anything specific somebody wants to look at just ask me and I’ll send it on.

> [16:57:47] [Server thread/INFO]: [Server] Server shutdown in 10 seconds! Saving.. probably is not a minecraft built-in message. You can see the server “speaks”: [Server]. That’s done by the /say command or by a plugin/mod. Please post a screenshot of your mods folder or write a list of all plugins and mods.