Zeruel is a vaguely humanoid Angel slightly larger than an Evangelion, with a large, bulky body and prominent core. The core is rather large relative to Zeruel's body, and the S² Engine within may be, accordingly, "oversized", perhaps accounting in part for the discrepancy in power between Zeruel and other, similarly sized Angels. Zeruel possesses a protective lid-membrane capable of shielding the core when threatened, and it serves as a testament to Zeruel's incredibly tough constitution: even when an N² bomb is detonated in direct contact with the (protected) core, not only is the red sphere left completely unscathed, but the rest of the body is, as well.