Luckily it can be cast cheaply by sacrificing four Eldrazi Spawn instead
There's a lot of solid stuff that makes it pretty decent, though not necessarily top-tier among the Season spells
Anafenza, the Foremost Anikthea, Hand of Erebos Betor, Ancestor's Voice Betor, Kin to All Bilbo, Birthday Celebrant Colfenor, the Last Yew Doran, Besieged by Time Doran, the Siege Tower Felothar the Steadfast Felothar, Dawn of the Abzan Ghave, Guru of Spores Ixhel, Scion of Atraxa Karador, Ghost Chieftain Kathril, Aspect Warper Kethis, the Hidden Hand Myrkul, Lord of Bones Narci, Fable Singer Nethroi, Apex of Death Nethroi, Apex of Death Tayam, Luminous Enigma Teneb, the Harvester Thalia and The Gitrog Monster The Necrobloom Vishgraz, the Doomhive
The unique Ability on Unknown, called HAND, states that once during your turn, before you attack, if Unknown is in your active spot and you have 35 or more cards in hand, you can use this ability to just win the game
I also really love Glin, Dwarf Emissary for his ability to generate Treasure tokens, particularly helpful in color-fixing in a five-color deck