Yu-Gi-Oh Master Duel secret packs contain a variety of iconic cards from across Konamis popular TCG game
With Mavinda in play, your instants and sorceries that target have a free flashback cost, and that can be used to blink, to cast powerful combat tricks, or to cantrip with a card like Defiant Strike
If she even generates just one extra energy, that still can go a long way in empowering a deck
Though stubborn and manipulative, she will not hesitate to protect her friends, like when Warashibe poisons Anzu, Honda, and Jonouchi and when she resolves to fight for Honda's sake after believing him to have died
The market can change at the drop of a hat, and you're buying and selling at your own risk
Mechanics like kicker, offspring, and ward all ask more of you than the measly mana cost, and gifting is just one more example of it