Scuttle, known as Dream Rapia (ドリームラピア,Dream Rapia?) in Japan, has a blue body. Aqua element. Attacks by either launching Aqua Towers (Mega Man Battle Network) or pushing ice blocks straight ahead (Mega Man Network Transmission, Mega Man Battle Network 2-3).
Scutz, known as Dream Meraru (ドリームメラル,Dream Meraru?) in Japan, has a red body. Fire element. Attacks by firing either balls of flame (Mega Man Battle Network), fire bombs (Mega Man Network Transmission, Mega Man Battle Network 2), or streams of Fire Towers (Mega Man Battle Network 3).
Scuttler, known as Dream Bolt (ドリームボルト,Dream Bolt?) in Japan, has a yellow body. Elec element. Attacks by either launching homing Thunder balls (Mega Man Battle Network, Mega Man Network Transmission, Mega Man Battle Network 2) or dropping lightning bolts from above their targets (Mega Man Battle Network 3).
Scuttzer, known as Dream Moss (ドリームモス,Dream Moss?) in Japan, has a green body. Wood element. Attacks by either launching Wood Towers (Mega Man Battle Network, Mega Man Network Transmission, Mega Man Battle Network 2) or raising vines below its target's feet, trying to capture and drain the target's energy (Mega Man Battle Network 3).
These two are the strongest versions in the family.
Scuttlest, known as Dream Bit (ドリームビット,Dream Bit?) in Japan, was introduced in the second game. White body. No element. Has a Life Aura 2 -- aura that repels 150 damage in the second game, and Life Aura -- aura that repels 200 damage in the third game. Attacks by firing a large laser straight ahead. It has 300 HP in Mega Man Battle Network 2, but strangely reduced to only 200 HP in Mega Man Battle Network 3.
ScuttleΩ appears only in Mega Man Battle Network 3. Black body. No element. Has a Life Aura. Attacks by firing a large laser straight ahead. Has 400 HP.
In the first game, the first four were only found with the Life Virus, the final boss of the game. They emerged from holes in the front row of their grid (also preventing any changes to that column), attempting to line themselves up with MegaMan and attack with the element corresponding to their color.
In this game, the first four all appear in the Undernet. Their attacks were somewhat changed, with the Scutz shooting off fire bombs and the Scuttles launching ice blocks, and they now have Life Auras like their master. They were also finally named in this game. There is also a new version called the Scuttlest that has an enhanced Life Aura that is even stronger then the Life Virus' aura.
Much like the previous game, they were found in the secret area.
These viruses also, amazingly, have their own Virus Chip. Their attacks are pretty much the same, but the Scutz' attack homes in on enemies automatically, the Scuttler launches bolts that hit enemies simultaneously, and the Scuttzer's vines attack from below, like PlantMan.EXE, only hitting once in the initial strike but doing tremendous damage when doing so. The "Boss", a ScuttleΩ, can be found in a hidden jack-in in Wily's Castle. Right as you get off the boat, go towards the opening in the wall and Jack-In. Its in one of the corners. BEWARE: This is probably the hardest Virus Boss fight in the game! But the payoff is worth it- it does twice as much damage as the Scuttlest's laser, doing a whopping 200 damage.