Shy Guy Stack
From the Super Mario Wiki
Shy Guy Stacks are a type of enemy appearing in Paper Mario: Color Splash. A stack of Shy Guys is formed when multiple Shy Guys group up, forming a stack. They appear in two varieties, 4-Stack and 5-Stack, and their health is represented by the number of Shy Guy's in the stack.
Shy Guy 4-Stacks appear in Cherry Lake, where one can be seen bullying a Shy Guy. Shy Guy 5-Stacks appear in Cherry Lake and Daffodil Peak. One appears on Vortex Island in the line of enemies that fight Mario after he squeezes the Washing Machine, and five appear in Fort Cobalt, where they are commanded by a Snifit to attack Mario.