Spell Stutter is another counterspell that becomes more effective as you grow your fae realm
Wait until you have enough mana and cards to lock down your opponent and win the game
Here's a list of our personal highlights for each set, but there is much more available

Brago, King Eternal Ultimate Masters Guilds of Ravnica Niv Mizzet, Parun, Emmara, Soul of the Accord, Lazav, the Multifarious (decklist in the comments), Tajic, Legions Edge, Etrata, the Silencer, Izoni, Thousand-Eyed Commander 2018 Aminatou, the Fateshifter, Xantcha, Sleeper Agent, Lord Windgrace, Brudiclad, Telchor Engineer Core Set 2019 Sai, Master Thopterist, Goreclaw, Terror of Qal Sisma, Vaevictis Asmadi, the Dire, Chromium, the Mutable Battlebond Dominaria Teshar, Ancestors Apostle, Grand Warlord Radha, Arvad the Cursed, Muldrotha, the Grave Tide, Slimefoot, the Stowaway, Yargle, Glutton of Urborg, Squee, the Immortal, Firesong and Sunspeaker, Jodah, Archmage Eternal, Tiana, Ships Caretaker Masters 25 Rivals of Ixalan Azor, the Lawbringer, Etali, Primal Storm, Nezahal, Primal Tide, Zacama, Primal Calamity, Tetzimoc, Primal Death, Zetalpa, Primal Dawn, Ghalta, Primal Hunger Unstable Grusilda, Monster Masher, Dr

Nevertheless, the fusion is worth it as it cannot be destroyed by battle with either a dark, earth, fire, water, or wind monster
Crobat ex has a tanky HP pool of 170, meaning there wont be too many cards that can knock it out in one go