Gotchawrench

A Gotcha Wrench is a living metal wrench. It has huge teeth to attack, and dinosaur legs to help it climb around.

Wrecking Crew (NES 1985)
Gotcha Wrenches appear on the first stage of the game Wrecking Crew. A Gotcha Wrench climbs around the construction site chasing Mario. They come in two colors; the purple variety is faster than the red.

Wrecking Crew '98 (Super Famicom 1998)
Gotcha Wrench is the fourth challenger in this modern Wrecking Crew update. Gotcha Wrench is purple and looks the same as it did in the original. It also appears in the remake on the same cart.

Names
In Japan, the Gotcha Wrench is known as the Spannagon. The name "Spannagon" is a portmanteau of the word "spanner" (another name for a wrench) and the word "dragon".