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In various locations within the game you can see billboards advertising Tricell, a pharmaceutical company from Resident Evil 5.
Contributed by Mass Distraction
After the ending credits, there is a morse code conversation between two unknown people. The first massage says "Vault facility occupied. Project Vulture Sentry System has been disabled. Awaiting instructions." The second is a German sentence, that when translated says "Confirmed. Implementation of phase Two. Activate project ALBATROSS." This was meant to set up for a sequel that (at the time of writing this) has yet to be announced.
Contributed by gamemaster1991