Depends on Who You Ask Yes, its great for new players to have access to many jumping-in points, and for budget-minded players who want to play powerful cards on the cheap
Part of the trouble is that nobody knows for sure how rare it issome small percentage of Miku Secret Lair drops contain a copy of this card (or its Rainbow Foil version) as a random bonus to go along with the other cards in the box
For seven mana you get an on curve 7/7 with four powerful keywords - flying (evasion), vigilance (very strong in multiplayer swinging at people in the air for Commander Damage and then holding the fort), deathtouch (no one wants to block) lifelink (nice double life swing for that 7 damage.)
Mystic Remora presents a trade off: do you want the cards, or the mana to cast them
If Scourge of Valkas is on the battlefield, he'll do damage to a target equal to the number of creatures you control, as they'll also have all creature types