I just spoke with GJ, it's not an attack. Apparently the algo that calculates the nethash is finally recognizing the hash a lot better lol. This is mostly Clevermining, but contact was made with the multipool and they've agreed to slow down the NLG mining until Digishield has been implemented. So no worries, as GJ said to me.
Are we able to confirm where the spike in hash rate came from now?
Digishield will need to be implemented ASAP, I think the coin has gotten a lot more attention this last week and you will find other multipools have joined the party besides Clevermining. It's good the devs recognised the need for this change and working on a solution but if this same spike has to occur each time difficulty drops then digishield will need to be implemented within the next few days.
The next block resolve could be as much as 15 hours by my estimations.
Also Doge and Litecoin have now got merge mining making multipools switch to other scrypt coins more aggressively.