I just tried the new river raid mode 3 separate times today. The first two times my character got sucked into the nearest wall, whilst I was opening chests. The third time I performed a 'stomp' on and enemy; I went right through the ground, died, and had to restart.. Again.
Hello there @michigan221fan! Welcome to the forums 
I'm sorry to hear that you've been getting stuck in walls and floors whilst taking part in the new River Raids. Can you let us know the locations where these incidents occurred?
If you have any videos that show this behaviour happening in-game, would you be able to send them to us so we can forward them for a closer look? I'd recommend uploading the videos to a sharing platform, such as YouTube or Google Drive, as this will allow you to post a shareable link within this thread.
Thanks! 
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