There's no mining in RaiBlocks.  If there is a disputed transaction, the "representatives" vote on which is right.  Each vote is weighted by how many XRB are associated with that representative. Right now the devs control the vast majority of the votes.

Representatives are expected to be always online and help secure the network, but there's no incentive for them to do so, which is the problem.

https://bitcoinbeginner.com/blog/what-is-raiblocks/