Echowell

Floodwater has swallowed the sinkholes around the village and cut the underground shelters off from the surface. You inherit the last listening station and a three-horn echo array. Your task is to place the brass listening rigs around each rim, compare their return paths, and locate hidden air chambers before the rescue line descends. Every sounding begins with a readable action: drag the highlighted horn onto its marked anchor, choose a low, mid, or deep band, and pull the cyan beam toward the target. When all three paths form a stable intersection, sound the well and watch the echo shells travel through the cutaway. The shipped campaign contains four regions and 40 sinkholes, with four soundings in every level. Difficulty rises from open baselines to layered water, occluding rock pillars, absorbent stone, inherited rig layouts, paired chambers, rescue routes, and four Grand Cenote milestones. North, Cutaway, and South section views help you compare depth and front-to-back obstruction. They are deliberate inspection angles, not a free camera, and the game never requires two-finger gestures or gyroscope control. After each successful sounding, Resonance Brief presents three field orders. Choose information, efficiency, or additional risk for the next descent. Briefs can reveal useful traces, carry selected settings, alter a frequency constraint, or hide a clue in exchange for a better reward. They never aim a horn for you and never reveal chamber coordinates. Accurate work earns Sounding Cord, Depth Seals, and Chamber Echo records. Chamber Atlas preserves located chambers, rig configurations, rescue notes, and ambient returns, and lets you replay completed soundings. Rewarded advertising is optional and limited to recovery or reward acceleration: restore the latest sounding, redraw a Brief, claim daily Depth Seals, or double a completed report. A failed or unavailable ad never blocks play. There is no forced energy system, no paid answer, and no advertisement that auto-solves a chamber. Interstitials are only attempted when returning from Survey or Atlas to the lodge and remain subject to cooldown. Every result is calculated by the deterministic EchoTriangulationSolver from anchor placement, bearing, depth, frequency band, water layers, and rock obstruction. The visuals are captured from the real Godot mobile compatibility build, and the shells and rescue animation present that same result. Echowell is an offline single-player spatial puzzle, not a promise of real-world acoustic simulation, free-roaming cave exploration, or online multiplayer.