Marvel Comics have released a teaser for December's Venom #21 which refers a classic Amazing Spider-Man storyline featuring Venom.
The teaser image starts with "Alas...." then features a humanoid skull being enveloped by a black symbiote. It's floating above an island, which is referenced in the bottom text "Venom Island". The teaser was released by Marvel along with the fuller copy "Alas Poor Venom..."
This would be alluding to 1991's Amazing Spider-Man #347 by writer David Michelinie and artist Erik Larsen. In this issue, Venom kidnaps Spider-Man to a secluded tropical island with the intent to have a final battle without fear of interruption. The unnamed tropical island was described a former mining colony that became uninhabited following a 1940s mining disaster.
At one point in the story, Spider-Man finds an unmarked grave with a skull dug up from the ground. Spider-Man eventually escapes by using the skeleton - garbed now in his tattered Spider-Man costume - to make Venom believe he had died. Peter Parker swims out to see and is picked up by a passing ship.
The "Alas Poor Venom..." is an homage to the cover dialogue for ASM #347, which reads "Alas, poor Spider-Man -- I killed him well!" - which in itself is a homage to a line from William Shakespeare's Hamlet.
Venom #21 is scheduled to be released this December.