I have two major survival builds, and both have been griefed by RJNJ. He has placed locked chests all over my main resource base, located X: 2111 Y:72 Z:-2460, as well as taking some tools i had up for decoration, blocking my mineshaft, and setting fires.
At a smaller build Located X:1578 Y:74 Z:-2386 i later found to be griefed in a similar manner. he seems to have gotten in via the nether portals. I have reported the resource base grief, but i didn’t find out about the other build until later.
I’m unsure if he thought that this was okay or if he was being malicious. I have mailed him a note explaining that he needs to undo what he did, but given he got two of my builds, I figured i should put this up anyway.