Final Fantasy IIs Firion, Wild Rose Warrior, gives equipped creatures haste (meaning they can attack immediately) and creates short-lived copies of your equipment when you play it
They add mana to your mana pool and do not use the stack
However, my favourite Team Rocket card ever released was Dark Celebi from Hidden Legends
Sword of Hearth and Home can also be used to untap a creature that you attacked with, letting one of your creatures play at having vigilance
If you're playing casually, theres nothing stopping you from adding them to your deck, but if youre considering following a tournament format, you should check which cards are banned
Green-White Go Wide Build up a large board of creatures, then swing in for the win with the power of your united forces