Teferi's last ability means that in order for an opponent to cast a spell, it must be that opponent's turn, during a main phase, and the stack must be empty
I expect this to become an interesting card to reanimate since you always get a solid two-for-one, but Im not sure I want to spend 9 mana on it
If youre interested in creating your own custom deck of playing cards, then you need to learn the basics of playing card design
Regenerate can pretty much keep your creatures alive given the proper resources, unless your opponent drops a regeneration-preventing nuke like Death Pits of Rath
The Assassins Creed set does also feature support for legendary and historic cards as another possible theme, and by focusing on those we could make a stronger argument for a mixed assassin/pirate creature base
Grindstone + Painter's Servant infinite mill, Blue Sun's Zenith with pili&grand make them darw all cards