They have a great Viking raid system which works really well and added a dedicated River Raids mode which sees you trying to get as far along the river exe (and Severn iirc) as you can each time, trying to judge how much you can handle, whilst managing your little group of Vikings. If any of them get injured they’re out for the rest of the raid and won’t be available for your next one.
The more you raid one river, the more defences the settlements build up. So you’ve got to manage that aspect as well; ploughing resources back into your Vikings so that they’re able to handle the tougher, more lucrative forts and the like.
It’s a great little diversion IMO.