Nartors Ring is an exclusive SpltinterForge pre-sale airdrop card. Here is a sneak preview of the card stats that were posted by 
The promo card is a legendary ring that has 2 advantages, first is that it starts with 2 sockets instead of 1. Sockets can only be added with Electrum which is only obtained through fighting or burning cards which give anyone with the promo card a head start.
The big advantage is that, besides Nartors Ring, the ring equipment slot won't be obtainable until the 800k pack distribution airdrop. So, until there are 800k packs distributed, only people with the promo card will be able to fill that equipment slot (which also happens to be a speed stat slot).
How do I get Nartors Ring?
Nartors Ring is an exclusive airdrop available only during the pre-sale.
On launch, anyone who purchased CRATEs during the pre-sale (December 5th has a 2% chance to receive Nartors Ring, a legendary ring card that starts with 2 empty sockets. Pre-sale buyers are guaranteed 1 drop per 50 CRATEs purchased.
This card is only available via the pre-sale airdrop and will NOT be available in CRATEs.
For more details on the SplinterForge.io pre-sale and launch details, check out the full announcement post.