Like most Magic: The Gathering cards, the value of Mystic Skyfish depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Core Set 2021)
A single board wipe would not only reset the battlefield, but remove all of your acceleration
in a sense, it's not too much of a stretch to see these as official proxies
Academic Dispute Accelerate Aleatory Ancestral Anger Balduvian Rage Blindblast Bloody Betrayal Boiling Blood Bonfire of the Damned Chandra's Defeat Chaotic Strike Crimson Wisps Cunning Maneuver Deem Worthy Ember Shot Enthusiastic Study Expedite Fiery Encore Fire Prophecy Fires of Victory Fists of Flame Flamethrower Sonata Flare Go for Blood Hammer of Bogardan Impolite Entrance Incinerating Blast Jet's Brainwashing Lacerate Flesh Limits of Solidarity Manhole Missile Might of the Meek Mishra's Command Molten Frame Needle Drop Neonate's Rush Nibelheim Aflame Orcish Cannonade Panic Psychotic Fury Pyrrhic Blast Raking Claws Renegade Tactics Resounding Thunder Rile Shredded Sails Solar Blast Spark Spray Stun Take Out the Trash The Chase Is On Thunderous Wrath Torch the Witness Vengeful Possession Volcanic Spite Wildfire Howl Witch's Mark Zap
There arent too many legendary slivers, but the ones we have can pack a punch
2 Tatyova, Benthic Druid One of the best uncommon creatures around, Tatyova, Benthic Druid is, as you might expect, a Druid