Ultraman Gaia

Gamu Takayama, a young genius performing experiments involving human consciousness, is drawn into a strange world where he sees a giant battling a monster; meanwhile, a wormhole unleashes a wave of invaders on Earth.

After struggling through his first battle as Gaia, Gamu is somewhat forcibly drafted into XIG; it soon becomes obvious that not all threats to Earth will be arriving from outer space.

A jellyfish-like monster with incredibly destructive powers seems to be immune to conventional attacks.

When Gamu is baffled at how the monstrous Gan Q seems to defy the laws of physics, his faulty instructions cause the XIG offensive to go wrong.