We do not print official card backsour backs are designed to be clearly non-official
It's okay if any of them are already tapped, and it's okay if any of them are controlled by someone other than the defending player
A few decks were able to squeeze wins on the play against Elspeth, by making sure she could not be cast: While this deck didnt win, it was able to shine to a degree because of the banning of Strip Mine, meaning it could rely to some degree on keeping a land alive, and thus casting Cenns Tactician and putting lots of +1/+1 counters on it
The damage is still dealt for purposes of effects that care about damage, such as lifelink
Being a type of artifact token, it also counts for cards that count token artifact types, such as Gimbal, Gremlin Prodigy or Tawnos, Solemn Survivor