Saw this one on the proposal needed for Silly NPEs, so I think she could have a shot.
What's the Work?
The Lorax is a 2012 animated film by Illumination. It is an adaptation of Dr. Seuss' 1971 book of the same name.
Who is She? What Has She Done?
The Once-Ler's Mother is the overarching antagonist of the film. She is the greedy, manipulative and emotionally abusive mother of The Once-Ler who is single handedly responsible for him tearing down the Truffla Forest and destroying the environment.
So she first appears in the film as constantly bullying the Once-Ler along with the rest of the family when he chooses to go down the path of business. This motivates the Once-Ler into leaving and starting a Thneed production business in the Truffla Forest, with the Thneeds becoming very popular. After his success, the Once-Ler contacts his mother and the rest of his family, and they ride over to his base of operations. The mother also appears to start acting proud of him, becoming the Vice President of the Thneed company. Later on, she convinces her son to go full throttle with making the Thneeds to further his business, and she likely knew that this would result in the destruction of the entire Truffla Forest. Her manipulation over the Once-Ler ends up succeeding, as he begins the process of chopping down the entire forest while singing well-known "How Bad Can I Be?" song, where she helps the rest of the family chop down the Truffla Trees. This results in the entire Tuffla Forest getting destroyed, and the air getting polluted. It is clear that at the end she only cared about the money she gained from the Once-Ler's business, as later on she is upset at the Once-Ler after the last Truffla Tree is cut down which resulted in his business failing, and she expresses her disappointment, immediately naming Brett as her new favorite child, showing she never truly cared for the Once-Ler after all and perhaps doesn't even care for her other two sons. She rides away into the horizon with her family and is never seen again for the rest of the film. Her actions would eventually lead to Aloysius O'Hare rising to power, with him releasing smog into the air so that people would have to buy more bottled oxygen from him, which endangered many lives, and he and his company also tried to prevent citizens from leaving Thneedville to discover alternatives to his bottled air.
Heinous Standards
Well, we do have The Once-Ler who personally carried out the destruction of the Truffla Forest himself. However, the mother as the Vice President of his company is the one who literally manipulated him into tearing down the trees as his superior while likely knowing that this would result in the demolition of the whole forest, showing that she directly kickstarted the destruction of the environment, so that could be enough for her to pass the standards. We also have Aloysius O'Hare, who tried to stop Ted from growing the last Truffla Seed, but he has more resources as he is the mayor of Thneedville and is in charge of a whole air company that manufactures bottled oxygen, so it'd be unfair to compare the Once-Ler's mother to him.
What Makes Her Silly?
She's literally a greedy scumbag meant to be a joke character. She also has some comedic moments, such as her scenes during "How Bad Can I Be?" and some of her conversations with the Once-Ler.
What Prevents Her from Being Pure Evil?
She suffers from some Fridge Horror, as it's unknown if the Once-Ler's environmental destruction by cutting down the Truffla Trees caused any deaths. Additionally, she was not directly involved in the destruction of the forest, as she only manipulated her son into doing it himself.
Verdict?
Not the strongest keeper out there imo, but your choice.