Well, thats up to six extra combats
It doesn't copy whether that creature is tapped or untapped, whether it has any counters on it or any Auras or Equipment attached to it, or any non-copy effects that have changed its types, color, power and toughness, and so on
This is a conversation for another post, but the bottom line is that there are fakes, counterfeits and resealed boxes and cases everywhere, even in Magic
It is best if you stay with the color of your first choice
This card tends to see play in decks that generate a lot of tokens because they can station the turn they come into play and later potentialize this land, or in decks that can easily cheat a big creature into play
The card also gives any other legendary and artifact spell flash, making you an unstoppable force once it hits the field