The Visage

The Visage is one of the bosses that can appear in Mausoleum. It is a more difficult version of the Mask of Infamy.

Phase One
Much like the Mask of Infamy, during the first stage of the battle the Mask and the Heart will act largely independently of each other, with the Mask attempting to chase Isaac and deal contact damage while the Heart tends to move away. However, the two are connected by a chain, and neither can be harmed directly. The chain must be damaged to progress the fight. During the first phase, the Visage has only one attack; the mask will charge at Isaac, sending out rocks upon colliding with the wall but not dragging the heart with it, stretching the chain in the process. This is usually the best point to strike as it makes the chain most vulnerable.

Phase Two
Once the chain has been destroyed, the second stage of the battle begins. Now the Mask has a visible hole in its back through which a purple flame can be seen, and both the Mask and the Heart can be damaged directly. The Mask can only be harmed by attacking its backside, but the Heart is vulnerable regardless of where it is hit. In Phase Two, the behavior and kinds of attacks used by the duo also change:
 * The Mask seems to charge at Isaac faster than before.
 * The Heart will flee from Isaac at a higher speed.
 * The Heart's main attack is to launch an extending chain, with different effects depending on what the chain hits.
 * If the chain hits the Mask, the duo will perform one of several attacks:
 * The Heart pulls the Mask over so that the Mask is directly adjacent to the Heart and facing Isaac. Then, the Mask will fire a pair of purple (but not homing) Brimstone laser in a double-helix pattern in the direction it is facing, from both eyes. When the Mask finishes firing this beam, the pair disconnect and each resumes its normal behavior. The Visage cannot use this attack if the Mask has been defeated.
 * The Heart quickly swings the Mask towards Isaac. The Mask fires non-homing purple tears in the direction it is facing while being swung, and launches rocks into the air when it hits a wall. If the Mask has been defeated, no tears are fired.
 * The Heart pulls the Mask to the Heart's location. The Heart then jumps up, dropping down on Isaac and releasing rock waves in an "X" formation along with several loose rocks when landing.
 * If the chain hits Isaac, the Heart will pull him in to do contact damage.
 * If the chain hits a wall, the Heart will pull itself to the wall, firing purple tears and rocks in all directions upon making contact.
 * If the Mask takes enough damage from behind, its fire will go out and it will stop moving and attacking. The Heart can still use the inert the Mask for its attacks.

Phase Three
Once the Heart has taken sufficient damage in The Visage's second phase, its stony surface breaks, revealing a glowing purple heart, and its behaviors are completely changed:
 * Sometimes, the Heart will fire a big purple energy ball that moves toward the mask, dealing contact damage to Isaac if touched.
 * The energy ball can be destroyed by attacking it.
 * If the energy ball contacts the Mask, it will fire a purple non-homing Brimstone laser from its back, propelling itself forward and launching rocks into the air upon colliding with a wall. If the mask was defeated before, it will instantly re-ignite in this process.
 * If 3 or more energy balls exist at the same time, the Heart may absorb all energy balls on the screen, then fire 4 short-range Brimstone beams in a diagonal direction, together with 3 tense rings of purple flame projectiles toward all direction.
 * The heart will occasionally fire a ring of purple tears in all directions that return to it shortly afterward.

Upon killing the heart, the Mask permanently stops moving and the fight will be over. Upon leaving and re-entering the room, the Mask will despawn.

Trivia

 * The Visage started as a boss versus screen mockup by Antibirth artist NotYourSagittarius in January 2015, alongside Reap Creep and a posthumous version of Dingle who did not make it into the final mod, "The Mass".
 * The Visage was conceived as a posthumous version of the Mask of Infamy.
 * Judging by the general theme of the Mausoleum where it appears, it's possible that The Visage is a posthumous version of the Mask of Infamy which was revived with necromancy.
 * When the boss is defeated, the Heart is destroyed like most bosses (leaving nothing but a pool of purple blood), but the Mask leaves behind a metal husk which can be nudged around like a stone chest. This object maintains the general appearance of the Mask and faces the same direction which the Mask faced when the boss was killed, but the purple fires which could be seen in its eyes and the hole in its backside have gone out and it no longer deals contact damage. It is unknown if this remnant of the boss is purely aesthetic or if it is related to some sort of secret, like the skull dropped by The Siren.
 * The Mask of Visage has a normally unused death animation that can be seen if the mask is shot with a Chaos Card after the fight.
 * The Visage's gender is currently unknown. However, if The Visage is based on Mask of Infamy, then The Visage's gender would be female.
 * The Visage has become a boss in The Binding of Isaac: Repentance, however it was moved to the alternate floor of the Mausoleum, known as The Gehenna, The Visage also got a color change to fit Gehenna more