Croire

Croire (クロワール) is a new type of Cyber-elf developed by Ciel and given to Zero in Mega Man Zero 4 after he defeats Carnage Force 0. She resembles satellite elves in that she can provide a passive boost to Zero's power without sacrificing herself, but she is far more versatile than other Cyber-elves, using her power to copy other elves.

Characteristics
Croire is a customizable elf, and presents an entirely different approach to the Cyber-elf system. Like the satellite elves from Mega Man Zero 3 she follows Zero and provides a passive effect without being sacrificed, but attempting to use abilities beyond the maximum limit penalizes the mission score. Croire's effect is set by changing which elves she is copying: selecting one elf each from the Nurse, Animal and Hacker types. At any time, she can copy one elf from each type, with a level less than or equal to her current elf level. By feeding her with E-crystals and leveling up the preferred type of ability, this Cyber-elf becomes more powerful as it grows through seven stages of evolution. Normally, elf effects do not usually overlap. However, if one of the three abilities is set to the highest level, the player will receive every preceding bonus in addition to the one listed for that level. Additionally, in ultimate mode, all the powers of the preceding elves will be active at once regardless of the set level (so using animal level 5 would also use 1, 2, 3 and 4).

Evolution
Depending on who the player talks to for the name, the Cyber-elf can be called one of the following things, each with its own unique benefits: The System has two variables, Elf Total and Elf Capacity. The former is the sum of the levels of all active abilities, the latter increases as stages are completed and by equipping the Elf Body Chip. If Elf Total exceeds Elf Capacity during a mission, the difference is deducted from that mission's score (somewhat like Fusion Elves in previous games).
 * Alouette will name the Cyber-elf Croire. It means "believe" in French. This increases the drop rate of Life Energy capsules for Nurse Abilities Lv. 1 and Lv. 6.
 * Ciel will name the Cyber-elf Charité. It means "Charity" in French. This increases the damage done by the Animal ability for Levels 3 through 5 by one point.
 * Rouge will name the Cyber-elf Variable. This increases the damage done by Animal ability Lv. 5 by two points.
 * Cerveau will name the Cyber-elf Progress. This increases the damage done by Animal ability Lv. 4 by two points.
 * Faucon will name the Cyber-elf Recrue. It means "recruit" in French. This increases the damage done by Animal ability Lv. 3 by two points.
 * Hirondelle will name the Cyber-elf Nouvelle. It means "new" in French. This increases the damage of the Hacker Lv. 2 ability by three points.

Effect
For each Elf type Croire copies, Croire will only copy the elf of the chosen level. So for example, when copying the level 7 Animal elf, Croire will cut the damage Zero takes in half, but she will not fire any bullets from the level 3, 4 and 5 Animal elves, nor will Zero get increased speed. But he may at the same time tell Croire to copy the level 3 Nurse elf (8 extra life), and the level 2 Hacker elf (upward slash in saber combo), and he will receive all three effects at once. In Ultimate mode Croire is enhanced and when she copies an Elf of any level she will also copy all the elves of the same type from lower levels as well (meaning when copying the level 3 Hacker elf, for example, Zero will have increased attack power, the upward slash and an increased rate of fire with the buster). Croire is disabled in Hard mode.

Trivia

 * Zero (and thus the player) plays a hand in naming this Cyber-elf. Alouette picks the name Croire, but if Zero doesn't like it, he can speak with the other Resistance members to come up with another name. Ciel comes up with "Charite," Rouge suggests "Variable," Cerveau settles for "Progress," Hirondelle recommends "Nouvelle," and Faucon offers "Recrue."