No, I haven't noticed the hoards of Nightmare users in DM, DT and TR.

What is this clan 'Nightmare' you speak of?

I think he means that he is having 'Nightmares' of running into the same clan over and over.

In my opinion, the most played clan in Deathmatch is Bangers.

Most popular clans in DM:-
Bangers
Nightmare
Sentinel
Ulu Watu
Uppers (usually half deck)

MarsiK- is right, Bangers is wayy to overused atm. Why isnt Rescue used much?

Rescue is not used much because of their lack of OP cards. I mean compare Cards like Tana to Marco. Not reliant on his ability to win.

And the fact that most of Ulu, Bangers and Sentinel are 4-5* cards which are OP and banned.

Given that most of the missions to earn Kreenk Ld take place in deathmatch rooms , it's little wonder they're popular at the moment . in the same way that the survivor rooms were full of Nightmare , and the warehouses full of candy jacks .

the Nightmare are still around in deathmatch because they're having a field day with their stop bonus against the over-proliferation of Bangers .

Rescue isn't used because you don't want to Rescue your opponent in battle, you want to beat them.
I mean for example they have so many + life cards how can they win a battle, seriously Suzie gives you 4+ life if she wins against you its ridiculous.