A "god tier" character is exceptionally powerful, unbeatable and above all others in strength and capabilities, aka someone comparable to Thor.
After Avengers: Endgame, Marvel Studios introduced a whole bunch of characters, and here are 10 of the most powerful ones:
Arishem the Judge (Eternals, 2021): Immense cosmic powers and role as the Prime Celestial who judges civilizations.
Infinity Ultron (What If...? Season 1, 2021): With all six Infinity Stones, he's nearly invincible, reshaping reality itself and posing an unparalleled threat.
Kang the Conqueror (Ant-Man and the Wasp: Quantumania, 2023): Kang can time travel, manipulate timelines, and has unparalleled technological genius.
Eternity (Thor: Love and Thunder, 2022): Eternity has unlimited ability to manipulate time, space, matter, energy, or reality.
Namor (Black Panther: Wakanda Forever, 2022): The Mariner has many powers, including superhuman strength, telepathy, and the ability to breathe underwater.
Ikaris (Eternals, 2021): He can fly, possesses telepathy, can cast low-level illusions, and can rearrange the molecules of other substances.
Zeus (Thor: Love and Thunder, 2022): Has astonishing resistance to damage, surviving his heart and other innards destroyed by Thor.
G’iah/Super-Skrull (Secret Invasion, 2023): Virtually invulnerable, with Asgardian genetics, a healing factor, magic, and super strengths of various MCU characters.
Doctor Strange Supreme (What If...? Season 1, 2021): Mystical powers, absorbing countless entities, and bending reality to his will are his key strengths.
God Loki (Loki Season 2, 2023): Mastered time travel and weaved timelines into Yggdrasil, becoming the ultimate protector of the multiverse.