Fathom: Sonar Puzzle

Chart what the dark won't show. Fathom is a quiet sonar logic puzzle about deciding how much the next answer is worth. Explore a hidden grid one edge at a time, find each objective, and complete the mission using as little Intel as possible. PROBE THE UNKNOWN Test an unexplored direction for one Intel. An open route lets you move. A wall becomes part of your permanent chart. Once a corridor is known, traveling through it is free. CHOOSE YOUR SIGNAL Spend two Intel on a focused Sonar glimpse, or commit five to a wider Deep Pulse. More information can save a run—but only if it was worth the cost. THREE WAYS TO PLAY • Campaign: Twelve named missions introduce the rules and combine them in new ways. • Daily Dive: Complete a fresh Easy, Medium, and Hard sequence each day. • Free Dive: Generate another seeded chart whenever you want a new puzzle. THREE MISSION FAMILIES • Echo Hunt: Follow distance and bearing to a hidden beacon. • Relay Chain: Reach multiple relays in the correct order. • Sector Survey: Visit every marked objective and turn uncertainty into a map. PLAY AT YOUR OWN PACE There is no timer and no move limit. Fathom rewards observation, memory, and efficient decisions. Finish a mission, study the revealed chart, then return to lower your Intel score and improve your grade. • No ads • No subscriptions or in-app purchases • No account required • No analytics or tracking • Progress stored on your device • Left- or right-handed controls • Designed for landscape play on iPhone Move cheaply. Scan wisely. Learn the dark.