Velma's spider half consists of a huge green abdomen with six spider legs, spinnerets, and a yellowish stinger. On her human half she has pale skin, freckles on the both side of her pale cheeks, she also has black hair, a spider crown, blue lipstick,a blue collar, a sapphire blue shirt with no sleeves, and gloves. She also holds a scepter. She also has some freckles on her green abdomen.
In her teenager years she she wore a purple sweater, earrings, and pale skin with freckles, and glasses.
It is shown in the episode Wrath of the Spider Queen, in the flashback when Grim and Velma would interact, Velma was a overall nice girl. She seemed to be caring, and this was further shown when she stuck up for Grim when The Boogeyman gave Grim a wedgie. By sticking up for Grim she cocooned Boogey in her sticky spider silk, stung him, and stuck him on the school flagpole.
In the special, Velma still seems to show her nice and kind personality, but she develops and vengeful, mean, and slightly evil personality. This change was based on the fact that she thought Grim cheated when he was chosen to be a reaper. However, she found out that her name had been in the basket he had been dumping into the voting cauldron due to Grim thinking that she deserved to win the most, and upon discovering this, she apologized to Grim and went back to her kind self.
That is, until Jeff cancelled the wedding.
She is very agile and durable, can temporarily paralyze her victims by stinging them and can shoot thin strands of adhesive webbing from her spinnerets. Apparently , her face and cheeks turn red when she uses her webbing.
- Spider Queen's Song: A very beautiful, soft, melodious and angelically irresistible non-lyrical vocalized songs and melodies that Velma uses to musically summon and attract other spiders to her. It may be a musical/sound/vocal-based ability only Velma possesses. Or maybe all female spiders-centaurs can do it, all we know is that it's hypnotic musical sounds is strong enough to call spiders from all across the globe.
- Web shooting: An attack that Velma uses she shoots strands of spider web silk to cocoon her victims and can even shoot from from afar. She used this attack on Boogey and Mindy.
- Stinger: Another attack that Velma uses. At the end of her abdomen she has a yellow stinger that is used to paralyze her cocooned victims. This attack was only used on Boogey.
- Agility: Velma can run, jump, and move fast.
- Cocooning Victims: When Velma cocoons her victims they are unable to move and stuck in the cocoon.
- Hissing: Velma usually hisses at people who assault her.
According to one of the writers, when she was a baby, she had a habit of sucking on her pacifier and hugging her Teddy Goblin (looking like the same as she was as an adult but with a diaper) and if anyone took them, she would cry and attack them, take them back and continue sucking on and hugging it. And as a kid, she loved eating people who accidentally sneeze on her.
Velma was once Grim's best friend during their days at Doomsday Junior High together, but their strong friendship later dimmed when Velma thought that Grim had cheated to be the Grim Reaper (in reality, Grim had tried to help Velma win.) She was Jeff's fiancee and bride-to-be, but Billy told Jeff she wasn't good enough for him and Jeff canceled the wedding.
She swore to avenge herself against Grim whom she thought had betrayed her and was voting for himself to win. However, Mandy learned the truth and she showed Velma how wrong she was for falsely accusing him of cheating when a stray paper revealed her name, which made her cry. Grim revealed that all the votes were for her because she would've made the best reaper in their school. Velma renews her friendship with him when he told her the truth of what really happened on that day. Grim found out that the teenage Boogey Man was afraid of losing to her and continued cheating by putting more votes for himself so he can embarrass Velma after she lost. Enraged, he unleashed a terrible display of his supernatural powers--stemming from all the pent-up inner rage that she had once assured him that he had inside himself all along--and banished his long-time bully for trying to embarrass Velma which lead to everyone who hadn't already voted to vote for Grim instead. When he asked her what she was going to do next after Jeff called off their wedding, she said she has nothing else to do but rule the world like her dad (Skippy) wanted her to. Her mother had thought that she had the dominating ability to rule two worlds.
- Her name is a play on Vanna White, the hostess of Wheel of Fortune.
- Velma has a yellow stinger that was used on Boogey to paralyze him, however spider's in real life don't have a stinger.