Trench Wall

Clear three rows to repel the trench beast before rising rubble crushes the wall. Tap a column to drop one stone. Each full row deals two damage. The tentacle raises a new rubble row after every second drop, with its gaps previewed in the HUD; once the beast has only two health left, it rises after every drop. Incomplete rows can be lifted above fresh rubble, so finish their exposed gaps rather than looking only at the bottom row. Each rise that pushes occupied cells off the top costs one of three hull. One Brace cancels the next two scheduled rises, and one Vent removes the bottom row without damaging the beast. These emergency tools preserve space, but using them too early can delay useful gap patterns. Keyboard: Tab and Enter/Space operate buttons; R restarts.