The Underwater Labs Add-on for Escape Dead Island has 10 achievements worth 245 gamerscore.
Find all the underground secondary areas
Kill 100 enemies with the assault rifle
Complete the underground labs
Collect all of Ronald's logs
Acquire the assault rifle
Kill a Dweller using an environmental hazard
Stealth kill a Dweller
Kill 10 enemies at long range with the walloper
Acquire the walloper
Find the underground labs