Anti-Venom
A teaser image of the Marvel Legends 2015 figures has been circulating the Internet and includes Anti-Venom:
Looks like you will be able to add another symbiote to your collection some time this Spring. Ultimate Spider-Woman (who also resembles Spider-Man's symbiote suit) will also be available in this collection.
[Thanks to everyone who notified me about this. Sorry it took so long to actually post]