The action description on the card states that when the player casts a noncreature spell they can put a +1/+1 counter on any other Dorat cards, which due to the cards already having 1/1 stats would mean that the player would need to play a lot of the same Dorat cards to be any threat to their opponents.
Jace Reawakened sees the previously Phyrexianed hero becoming a two-mana blue planeswalker who cant be cast until turn four of the game
Lets take a look at the decks revealed from the Hyogo Championship Series and examine the key cards these top players included in their lists
In order to allow growing and shrinking, Richard reduced the creature's power to 0 (and the toughness to 0 as well on the Hydra) and had the creature come into play with some number of counters already on it
This deck has less two for ones than the Grixis list but it comfortably makes up for that with more and better tempo cards and way more dangerous games ending cheap threats
Cards like Spirited Companion, Deadly Dispute, and Kor Skyfisher are great for triggering it reliably while that scaling ward tax makes Minthara harder to remove as it grows stronger