Word of God

There are, in fact, two spells for taming, one for wild animals and the other for dungeons, which differ very little in wording. In both cases, the tamer has to ask the planet, which can be expensive depending on geography and what else the planet is doing at the time, and links the life force of the tamed creature to the tamer. The tamer essentially starts paying the upkeep of the animal with his own mana. As a result, the tamed creature doesn't "need" food anymore, but not feeding it becomes tiring for the tamer (the double mana cost rule applies). The tamer's death kills the tamed creature, but not the other way around (it's only very painful). Through their link, the tamer can order the tamed creature around without words and know each other's general location, but they do not share senses or anything like that.

Boss monsters, already tamed monsters, named monsters and humanoid monsters cannot be tamed. A tamer can hand over a tamed creature to someone else, but it must be done personally. The offspring of tamed monsters are not tamed themselves. Anyone capable of asking the planet can tame a monster.

—Source: https://forums.spacebattles.com/threads/i-woke-up-as-a-dungeon-now-what-dungeon-worm.620521/page-157#post-48157633
—Archive: https://web.archive.org/web/20220618135419/https://forums.spacebattles.com/threads/i-woke-up-as-a-dungeon-now-what-dungeon-worm.620521/19/reader/?post=49010413#post-48157633