From the Super Mario Wiki, the Mario encyclopedia
The first time Luigi enters the Snake Chamber, it is filling up with sand, with Snakes and Hearts buried in the mounds. There is a statue in the northeast corner. To reach it, Luigi must use Bursts and other such moves to blow the sand toward the statue, creating a ramp allowing him to reach it. However, once he gets next to the statue, it drops down and the door is blocked. Snake statues appear in the southeast corner, northwest corner, and center of the room, aiming red lasers at the chains holding up the ceiling. If all three chains are broken, the ceiling collapses and falls, giving the player an instant Game Over.
To prevent this, Luigi must pile up sand to create more ramps allowing him to reach the snake statues, then use Bursts to deactivate them. After two snake statues are deactivated, a Slinker appears. Once all three snake statues are deactivated and the Slinker is captured, the room lights up and the statue in the northeast corner reappears. Luigi must investigate the statue to unlock the door, allowing him to escape the chamber.
If Luigi returns to the Snake Chamber after clearing the Tomb Suites, he might find vases buried in the sand. There may be a Boo in one of the vases Luigi must break open to reveal.
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