The set includes awesome cards like Jasmine, Desert Warrior from Aladdin, the Super Goof version of Goofy, and some deep cuts like Diablo, Devoted Herald - yes, thats Maleficents raven
Obviously a creature that gave +1/+1 to the rest of your team for two mana would be ridiculous (Im looking at you Wizened Cenn)
The exclusive MTG card won't be just jammed in there
You cant make choices or decisions for that player that arent called for by the game rules or by any cards, permanents, spells, abilities, and so on
Being green means that it probably fits in less decks than its counterparts, but being an elf comes with its own synergies, too
That being said, while there is a little bit of demand, as a sideboard card, Stronghold Gambit is hardly an unmissable must-have