Tet is the most powerful God in the world of Disboard. He likes to play games so he shapes the world to also revolve around games. In his pursuit of strong playmates, he meets a pair of gamers, the sibling duo of Sora and Shiro. They are the only ones that ever beat Tet in a game of chess.

Hoping to have more fun time together, Tet summons the siblings to his world on a whim but he doesn’t give Sora and Shiro any special mission. On the contrary, Tet lets the siblings roam free on Disboard doing whatever they want and never interfere with their activities. He does occasionally disguise as common folks to play around with the siblings but for the most part, he has enough fun just watching Sora and Shiro's latest antics from afar.

If Tet is a playful God, then Being X is a petty God. Being X is the one who forcibly summons the soul of a dead middle-aged salaryman from Japan and reincarnates him as a little girl in a war-torn world. So why would he do that? To turn him into a believer, that's why. Yes, it's quite petty, isn't it?

That's why instead of calling him a "God", the nameless man gave the all-powerful God the nickname "Being X" out of spite. But once the man turns into little Tanya, she proves to be a handful and a stubborn human who refuses to put her faith in God, so Being X decides to interfere with her fate and put obstacles in her way. One of the ways he goes about it is by granting miracles and powerful magic to a character named Mary Sue to act as the ultimate enemy for Tanya.

Makoto is reading a book in his room when he is suddenly transported into the realm of God. Apparently, he is chosen to be a hero for a world of swords and magic. When Makoto finally comes face to face with the Goddess, she quickly dismisses the idea of him being the hero because she considers Makoto too ugly, so she banishes him into a barren wasteland at the edge of the world instead.

Despite feeling betrayed and abandoned, Makoto still tries his best in this new and unfamiliar world, and for the most part, he manages to lead a rather fruitful life. Unfortunately, seeing Makoto so happy somehow pissed the Goddess so she begins to constantly get in his way, such as the time when she messes with Makoto's spell and teleports him into the middle of a demonic war. That animosity carries on until the end of the series because Makoto is constantly the thorn in the Goddess's side, or perhaps it's the other way around.

Hitogami, or the Human-God, is the name of the God who often appears in Mushoku Tensei. He is a mysterious being who resides in a dark void. Appearance-wise Hitogami looks very similar to the being that guards the Alchemy Door in the Fullmetal Alchemist series. They both have a blurry and opaque body but you can somewhat see their mouth when they talk.

Hitogami often appears in Rudeus's dreams and gives him various information that proves to be highly beneficial for Rudy, such as the time when he tells Rudy to help and trust Ruijerd or when he asks him to buy some food for a hungry girl who turns out to be a demon emperor that grants the demonic eye to Rudy.

That being said, behind his sweet words and helpful advice, Hitogami seems to have a secret intention in mind. Hitogami seems to aid Rudy because he has a certain plan for the boy. And as the story progresses, it becomes rather unclear whether or not Hitogami is a helpful friend or actually an enemy in disguise.

D is the name of the mysterious God who reincarnates Kumo and some of her classmates into the fantasy world. She appears to be an indifferent God who prefers to take a neutral stance on the matters of the world. But she somehow becomes quite fixated with Kumoko the white spider.

She follows Kumoko's struggle in the hellish underground dungeon gleefully. D also seems to be amused and rather impressed with Kumoko's achievements despite her limitations as a lowly spider. Which is why she grants a useful skill to Kumoko when she grumbles about how unfair the system feels to her.

But on other occasions, D purposely sets up various obstacles for Kumoko because she truly enjoys seeing Kumoko fight to survive. That is why D is without a doubt the most mischievous Isekai Gods of them all.