Against fast reanimator decks this might be better than No Mercy, otherwise, this is just an additional way to make people stay away from our red zone
Although Yuffie enters attacking when its ninjutsu ability resolves, it was never declared as an attacking creature (for purposes of abilities that trigger whenever a creature attacks, for example)
Fallout Precon Deck As such, the upgrade goals when adding new cards to the Science
In a 1-versus-1 game, Mangara slows down their game plan and keeps you alive longer, as they would likely stick to 1 attacker and 1 spell on their turn (unless theyre willing to let you draw)
As long as you controlled it when you began your turn you can attack with it
Time Spiral removes itself from the game, which does not allow you to infinitely recur drawing seven cards, as you would with Timetwister (see further down the list)