Mrs. Thwomp

Mrs. Thwomp is a female Thwomp in Mario & Luigi: Partners in Time and one of the bosses of the game. She is married to Mr. Thwomp and she is very easily angered. She lives in Thwomp Volcano. Unlike all other Thwomps, she is shaped like a boulder. She is also the first explicitly female Thwomp. Her battle style is similar to Trunkle, a boss from Mario & Luigi: Superstar Saga.

In the game, when Mario, Luigi, Baby Mario and Baby Luigi come to the volcano, it erupts. With E. Gadd's help, they were able to put the fire out. However, Mr. and Mrs. Thwomp waited each year for the volcano to erupt, but, when Mario and Luigi stopped the eruption, they became upset. As the brothers made their way to the summit, Mrs. Thwomp decided to take her frustrations out on them in a battle. During the battle, she uses an attack in which she seems to split into four and shrink, but it is revealed that some Micro Goombas help her as decoys when she shrinks. All of them have slightly imperfect disguises however, which the player can use as a clue to which to attack.

After being defeated, Mrs. Thwomp gets angrier, but her husband attempted to calm her down. Afterward, Mr. Thwomp offers to take the brothers into Thwomp Caverns.

Trivia

 * Although Mrs. Thwomp can only be defeated when she assumes her smaller form, in the American version of the game, the Mario Bros. are given the Coin reward for defeating her larger form, which is actually 0 Coins (as opposed to the 150 Coins assigned to the smaller form). This may have been a programming error, since in the Japanese and European versions of the game (which were released after the American version), the 150 Coin reward is assigned to the big Mrs. Thwomp, meaning the player will earn 150 coins after winning the battle, instead of Zero in the U.S. version.
 * She has a face that is similar to a Whomp.