Typically, a player defeats their opponent(s) by reducing their life totals to zero, which is commonly done via combat damage by attacking with creatures
Masterful Replication For about the same price, Masterful Replication is a somewhat better version of True Polymorph
Not enough punch for the places you want it and too few of those as well
The basic land types are Plains, Island, Swamp, Mountain, and Forest
Ugin, the Spirit Dragon may be a fair bit worse in the format
Before calculating the numbers, I assumed that the mythics would be lacking in value, mostly because the set is lacking the one really expensive mythic to help drive up the average value (while Gideon of the Trials is a chase mythic, at just over $21, it isn't the same as Liliana, the Last Hope, Chandra, Torch of Defiance, and the other uber-expensive case mythics we've seen in some recent sets)