Can't load pixelmon mod pack

[Phat Turtle]

Having trouble loading worlds for pixelmon. It immediately crashes back into the client after trying to create a new world. Log pasted here since the log was apparently too big for pastebin: https://paste.ubuntu.com/p/X4Sjc2mgRm/ 

[JaariAtmc]

oh, using beta stream for the launcher?

Just leaving this here:

[B#450] 2019/08/25 22:31:46 [INFO]  [22:31:46] [Client thread/FATAL] [minecraft/Minecraft]: Error executing task
[B#450] 2019/08/25 22:31:46 [INFO]  java.util.concurrent.ExecutionException: java.lang.OutOfMemoryError

[Phat Turtle]

18 hours ago, JaariAtmc said:

oh, using beta stream for the launcher?

Just leaving this here:

[B#450] 2019/08/25 22:31:46 [INFO]  [22:31:46] [Client thread/FATAL] [minecraft/Minecraft]: Error executing task
[B#450] 2019/08/25 22:31:46 [INFO]  java.util.concurrent.ExecutionException: java.lang.OutOfMemoryError

Sorry, I don't know what that means? 

[Munaus]

custom pack issue, not a problem on the launcher's part.
Moved to Platform Pagoda