Arkham Horror LCG: Horror in High Gear Mythos Pack: - Rules of Play says:

Continue to dive beneath the surface and investigate the twisted and strange happenings in the small fishing hamlet of Innsmouth! Following closely on the heels of The Innsmouth Conspiracy deluxe expansion, this cycle of Mythos Packs tells the remaining chapters of the story. From the mysterious heights of Devil Reef island to abyssal tunnels far beneath the ocean surface, players will have to go deeper than ever before if they are going to uncover the truth behind the cult's activities and safeguard the world from a rising tide.

Every new Mythos Pack in the cycle offers an assortment of new player cards for players to build and upgrade their decks, along with a brand-new scenario and the next chapter of The Innsmouth Conspiracy story in every pack. Venture beneath the choppy ocean waves, and uncover the secrets below!