It cant be countered, its a 15/15 flier with protection from colored spells (which means protection from most single-target removal), it can put your graveyard back into your deck then go back into the command zone when it dies, and it gives you an extra turn when you cast it
You won't put +1/+1 counters on it, but you will gain some life
I also find the Robin Hood synergy a bit weird
Youll notice from the card gallery, and the image above, that theres a foil Prince John Promo card in the Shimmering Skies set
If you're on the play, your best playline following Pluto on turn one would be to play Kit Cloudkicker on turn two , allowing you to bounce your opponent's turn one card back to their hand, giving your two characters on the board while your opponent has none
Not only that, but as its a card game, you cant go into battle with a set plan