Your ears are keenly attuned to faraway sounds in the water.
Benefit(s): You gain a +2 bonus on hearing-based Perception checks, and you reduce the distance penalty on hearing-based Perception checks to -1 per 30 feet at the water’s surface and -1 per 60 feet underwater. In addition, you can detect the location of creatures moving creatures in the water within 5 feet (or within 20 feet for creatures lacking a swim speed) as if you had tremorsense.
Alien Codex © 2018, Legendary Games; Lead Designer: Jason Nelson. Authors: Anthony Adam, Kate Baker, John Bennet, Eytan Bernstein, Robert Brookes, Russ Brown, Duan Byrd, Paris Crenshaw, Jeff Dahl, Robyn Fields, Joel Flank, Matt Goodall, Robert J. Grady, Jim Groves, Steven T. Helt, Thurston Hillman, Tim Hitchcock, Nick Hite, Daniel Hunt, Mike Kimmel Marshall, Isabelle Lee, Jeff Lee, Lyz Liddell, Jason Nelson, Richard Pett, Tom Phillips, Jeff Provine, Alistair J. Rigg, Alex Riggs, Wendall Roy, Mike Shel, Neil Spicer, Todd Stewart, Russ Taylor, Rachel Ventura, Mike Welham, George Loki Williams, Scott Young.