Silver-Fur Master grants so many options on its own, and it can turn an already-good ninjutsu deck into a near-unbeatable ninjutsu deck (so long as the draws are good, of course)
if you bring in Thoughtseize, keep in Blackcleave Cliffs, and if you bring in Prismatic Ending, keep in Inspiring Vantage
Doesnt everyone want a haste enabler
Control and midrange decks: These decks can use the protection turn to stabilize, then use the draw ability to stay ahead in longer games
A copy effect looks at the object in the game it is trying to copy, usually a permanent on the battlefield or a spell or ability on the stack, and uses that object as a template to determine what the copy should look like
Im sure some people are familiar with most of these things, but not with mailing best practices