Clam (Yoshi's Story)
From the Super Mario Wiki, the Mario encyclopedia
Clams, also called oysters, are enemies from Yoshi's Story. They act much like underwater Warp Pipes from Super Mario Bros. 3 by blowing air up (nonetheless, these actually stop after a certain amount of time). Clams are usually found around sea cacti. They are rare, and even then they only appear in Stage 5-2: Lots O'Fish.
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