Compared to the Angels which preceded it, Ramiel has a drastically different form and does not appear to be "alive" in a conventional sense, it appears to be a gigantic floating crystalline octahedron (two pyramids attached at the base, one on top and one on bottom). The surface of Ramiel is blue and highly reflective. A choral voice is heard singing a single F note repeatedly as it moves.
The Angel has a deadly directed beam attack capable of melting through an Evangelion's armor in seconds, and it can sustain the blast for a very long period of time, perhaps indefinitely. While most other Angel attacks remain inexplicable, Ramiel is shown activating an "Inner Torus Reactor", a type of nuclear fusion reactor, to power the beam. The beam is capable of hitting any target within the Angel's firing radius with perfect accuracy, and the Angel itself is capable of detecting threats coming up from underground as well as beyond its normal firing range. The potency of its attack makes Ramiel too dangerous to engage in direct combat with an Evangelion.
In addition, Ramiel has one of the strongest A.T. Fields of all the Angels, so strong that the naked eye can see it refracting light when it attacked.[3] The A.T. Field is quoted as needing a massive 180 million kilowatts (1.8 X 1011 watts) to penetrate. Combined, these potent defensive and offensive abilities make Ramiel a veritable flying fortress. Ramiel also possesses a drilling appendage which it can extend out of its main body, which it uses to drill straight down into the GeoFront itself.
However, the Angel is indeed biological. In the shots of the Angel being demolished in the following episode, bloody red squares are seen where the Angel's armor/surface structure is being taken off, indicating that it does have blood.