Prosperity allows him to turn each mana into two more mana (draw X off the Prosperity and then pitch each card to the Bloom for 2 each)
( Melds with Graf Rats.) Graf Rats 1B Creature Rat 2/1 At the beginning of combat on your turn, if you both own and control Graf Rats and a creature named Midnight Scavengers, exile them, then meld them into Chittering Host
This effect is already strong, but the Encore ability takes it to another level
In many occasions, youd refuse to make an attack if an opponent just played their big blocker and it isnt worth losing one of your creatures to it, but with this red commander at your disposal, you can remove the blocked creature from play and replay it post-combat so that you dont lose any value and still get through with the rest of your creatures
The drawback is, of course, that it will only target creatures
I mean, can you have too many Dragon decks in Magic