Miru Toraeru

Miru Toraeru (ミル・トラエル) is a yellow eye-shaped program from Cyber Peacock's stage, Cyber Space, in Mega Man X4. They are believed to be rogue anti-virus vaccines that are under Cyber Peacock's control. They still do what they were originally designed to do (purge foreign bodies of data found in the system), except they target the player's Maverick Hunter instead of Mavericks that have invaded cyberspace.

This enemy will capture X or Zero when they come into contact, cause 4 points of damage after a brief moment, then release the Hunter before disappearing. The majority of Miru Toraeru in the stage spawn "rolling" across the screen while the rest spawn stationary. They are impervious to regular attacks if they are spawned moving, but can be attacked if stationary.

Since reaching the end of an area on a certain time will reward different powerups, Miru Toraerus can slow down the player when trying to reach the other side of the stage on a set time. The best ways to prevent being trapped by Miru Toraeru are to use Soul Body (with X) or Kuuenzan (with Zero), both of which will "delete" the incoming programs. If the player has difficulty using Kuuenzan, Raijingeki can be used to repel the Miru Toraeru, which is good enough to avoid being ensnared by them, even though it won't destroy them.

Other appearances
Miru Toraeru appear in Project X Zone, where they are simply map obstacles that can be destroyed by a unit to clear paths. In Project X Zone 2, they return in greater numbers as map obstacles that can inflict a tremendous amount of damage to the unit that walks into their panel range.

They also appear in Rockman X DiVE, alongside a green variant. Their behavior is quite similar, however, they can be destroyed with a Close combat weapon.

Other media
Miru Toraerus appear in the Rockman X4 manga, where Zero runs afoul of them in Cyberspace. They engulf him, causing him to have a nightmare of Dr. Wily as well as fighting the former commander of the Maverick Hunters, Sigma.

Trivia

 * "Miru" means look, watch, view or see, and "toraeru" means capture, arrest or grasp. Therefore, its name can be translated as "Watcher Capturer".
 * Bindholder was named "Miru Toraeru" during development, and it is also able to hold the player's character.