The Engagement Ring (unofficial name) is an object in Bomberman B-Daman Bakugaiden IV. It appears in Episode 26.
Description[]
It is the ring that was created by Gray Bomber, that he wanted to offer to Ms. Purple as a declaration of love. The ring is a bit special, as it has power to detect Dark B-Da in the surrounding, and ultimately produce electric charges against them. As a result, when Ms Purple put the ring on her finger, she received a charge of electricity due to her Dark B-Da nature. Gray Bomber then removed it, and in the end no one ever made the connection, thinking it was a complete failure of his creation.