Bardiel

No one ever sees what Bardiel looked like before it struck. The Angel conceals itself inside a thundercloud, and its presumed true shape survives only as the fungus-like growth that spreads across Evangelion Unit-03 after contact. Once in command of the stolen unit, it warps that body freely, oozing infectious slime from the arms and stretching its limbs in an instant to nearly double an Evangelion's height.

What passes for a mind in Bardiel expresses itself through relentless forward motion and opportunism. It leaves a downed Unit-00 behind rather than finishing it off, pressing on toward Tokyo-3, yet it never misses a chance to propagate, seeping contaminated ooze toward any Evangelion it pins. It also guards its host jealously, physically blocking the ejection of the Entry Plug that appears to anchor its control. Though ranked below the strongest Angels in raw power, its choice of vessel makes it one of the most emotionally devastating enemies the pilots ever face.

The infection announces itself at NERV's secondary testing facility in Matsushiro, where Unit-03 goes rogue the moment its activation test begins. The possessed Evangelion levels part of the base in an explosion and starts walking toward Tokyo-3, prompting NERV to reclassify it as the thirteenth Angel and deploy Units 00, 01, and 02 against it.

Asuka falls first, her Unit-02 disabled the instant her attention slips. Rei maneuvers Unit-00 into a clean firing position from behind, but she cannot bring herself to shoot with Toji sealed inside the enemy's Entry Plug. Bardiel punishes the pause with a backflip that slams Unit-00 into the ground, then bleeds contaminated ooze down onto its left arm in a bid to spread. NERV saves Rei's unit only by detonating internal charges that blow the arm off entirely, an amputation the still-synchronized Rei feels as her own.

Shinji refuses to fight at all once Unit-01 confronts the creature, unwilling to gamble with the life of the boy trapped inside. Bardiel throws Unit-01 onto its back and elongates its arms to strangle it against a mountainside. With his son in mortal danger and still passive, Gendo Ikari orders pilot control severed and the Dummy System engaged. The autopilot drives Unit-01 to berserker-level ferocity: it snaps Bardiel's neck in moments, hurls the crippled body to the ground, caves in the skull, tears the frame apart, and finally crushes the Entry Plug itself, extinguishing what remains of the Angel. The plug bleeds when it ruptures, and NERV readouts in Evangelion 2.0 tag the substance around a plug in the parallel Rebuild fight as core-like, supporting the theory that the Angel's controlling mass rode inside the capsule with the pilot. Toji survives the anime version of the battle gravely injured; the manga shows him infected by the Angel directly, and there the encounter kills him.