When these abilities appear on the card text of a merged creature, they're considered to simply reference "this creature" instead

3 Blind Seer Boris Devilboon Braids, Conjurer Adept Cabal Patriarch Cadric, Soul Kindler Celes, Rune Knight Circu, Dimir Lobotomist Cynette, Jelly Drover Damia, Sage of Stone Deekah, Fractal Theorist Derevi, Empyrial Tactician Donal, Herald of Wings Dralnu, Lich Lord Dynaheir, Invoker Adept Emet-Selch of the Third Seat Emet-Selch, Unsundered Emry, Lurker of the Loch Endrek Sahr, Master Breeder Ertai Resurrected Ertai, Wizard Adept Ertai, the Corrupted Eruth, Tormented Prophet Esper Terra Eutropia the Twice-Favored Fandaniel, Telophoroi Ascian Felisa, Fang of Silverquill G'raha Tia, Scion Reborn Gadwick, the Wizened Gale, Waterdeep Prodigy Gandalf of the Secret Fire Gandalf the Grey Gandalf the White Gandalf, Friend of the Shire Gandalf, Westward Voyager Gandalf, White Rider Garth One-Eye Genku, Future Shaper Geralf, Visionary Stitcher Ghen, Arcanum Weaver Ghoulcaller Gisa Gisa and Geralf Gisa, Glorious Resurrector Glarb, Calamity's Augur Gogo, Master of Mimicry Gogo, Mysterious Mime Golbez, Crystal Collector Gorion, Wise Mentor Grandmother Ravi Sengir Grandmother Sengir Hakim, Loreweaver Haldan, Avid Arcanist

They essentially all give you two extra turns, which is exponentially worse for your opponents
If it could be hybrid, it was uncommon, and if it wanted to be a traditional two-color gold card, it had to be rare
The Spacecraft's ability in practice introduces numerous decision points to a game
Its important to note that the Trainer cards are not tournament-legal right now, but the Radiant Tsareena card currently is