Developers at Motion Twin / Evil Empire have announced Dead Cells: The Queen and the Sea DLC that will be releasing in early 2022 (Q1) and it has a teaser.
The developer has said it will cost $4.99 at release, which will help continue to fund another year of free updates for Dead Cells along with the next project from Motion Twin. The Queen and the Sea finishes the path started with The Bad Seed and Fatal Falls, giving you a new ending to the game.
"Battle your way through sunken shipwrecks, scale a soaring lighthouse and confront your deadliest foe yet. If you manage to make it through all that, maybe you’ll finally get off this god-forsaken island...
This late-game content will give you an alternative to the High Peak Castle/Derelict Distillery and Throne Room biomes."
While they said it will get another year of free updates, that's pretty much the minimum they're going for. Sounds like they will go longer if the game and DLC continue selling well enough and they only just did a big cross-over.