Quick overview at this moment:
Use this list as a starting point to see if you can find other links between them. Do not use my list as absolute proof. It is very common for two users to use the same IP at one point or another; 364 users have used the same IP as master-p, and the vast majority of them are not the same person.
The blackmail attempt appears to actually be done by
mrbigA, which is a different handle from MrBig (I have no clue if they are the same person or not).
It also looks like that ShameOnYou was sold to komodovpn on Aug 8, 2014 by ACCTseller using escrow.ms as escrow. Since komodovpn has not yet been linked to master-P (and I would somewhat question master-P's ability to create a altcoin/scamcoin), I might put these two accounts in a separate category. I was in contact with one of the victims of the scamcoin prior to bittrex releasing the funds in escrow to the devs, and apparently essex343, and HarryT1923 were also involved in the scamcoin, although I did not look at the connection closely (but it appears the other two accounts were likely farmed by the same person who had previously farmed ShameOnYou prior to me purchasing it to resell).
I would say there is probably a decent change that the address/location of komodovpn is similar to that of master-P
malaimult was sold to me by berserkerbarrage, and this may be a false positive. Although I am unable to locate who I sold this account to as they never quoted the account name I sent to them so it is not showing up when I attempt to search for it in my inbox.
jeffersonairplane had received positive trust from IronMarvel, and master-P, and had commented in both the master-P escrow thread and the scam accusation. It currently has positive trust ("Dark Green") both using DT and my custom trust lists. Interestingly, it also has personal text saying to always use multi-sig escrow