Fathom Hunt: Sonar Sub Search

Read the fleet list, compare the sonar counts and fire torpedoes only where a drone-sub must be. A ping counts the occupied cells in a 3 by 3 area around its centre. Sinking a drone reveals its outline and the empty water around it, which narrows what is still possible. Reefs mark known empty water, and thermal layers hide cells from the sonar count. Pencil marks let you note a suspected sub or suspected water. They never change the truth. The 120 puzzles are in five seas of 24: Sheltered Sound, Reef Channel, Cold Shelf, Thermal Basin and Deep Trench. The grid grows from 8 by 8 to 12 by 12 cells as you go. Clear one puzzle to unlock the next in a sea, and clear 18 to unlock the next sea. Torpedoes and normal pings are limited in each puzzle. Every puzzle can be solved within the free budgets, without Deep Ping, ads or purchases. There is no timer and no energy. Once you clear puzzle 24, each device date also brings a daily puzzle. Retries keep the date and your rewarded offers. The game contains mild fantasy violence against unmanned, fictional drone-subs. There are no people, no blood and no realistic weapons. The game contains ads and offers in-app purchases. An interstitial ad called Patrol break can appear only when you leave the results screen. It never appears before your fourth won puzzle, never more than once every two wins, and never less than 120 seconds apart. Failed puzzles and quits do not count. It never appears during play. Rewarded offers are optional and labelled: +2 torpedoes when your torpedoes run out, once per puzzle, and Deep ping in the sonar toolbar, once per puzzle. Remove Ads is a one-time purchase that removes Patrol break ads; rewarded offers remain. Deep Ping ×10 is a pack of ten Deep Ping tokens. The game is for players aged 13 and over. It plays offline. The internet is used only for ads and for purchases through Google Play.