Yes, the tokens are exiles at the end of each turn but it only takes one turn with a spell-like Burn Down the House to be played and the game is all but lost
Getting hit with such a huge decrease in power can shut down plenty of attacks, making Tiana a valuable card for protecting your other character
If a creature enters the battlefield as a copy of a face-down creature (or if a token is created that's a copy of one), that copy has the same characteristics as the face-down creature (in this case, it's a 3/3 creature with the two abilities and no other characteristics), even though the copy is face up
I want all my discard here
By paying one white mana, you can sacrifice Implement of Improvement to gain two life
But it also runs plenty of hand disruption, which should ensure you can stop your play pattern from getting messed up