Floshell

IronShield are a family of viruses from Mega Man Battle Network. They resemble a mechanical lizard except the tail (wherein they have two antenae portruding upwards). These viruses also have a shield throughout the battle, which makes them invulnerable to attacks. However, when the shield takes substantial damage, it gets knocked upwards, exposing the virus and giving the player a chance to strike before it lowers it again. The viruses attack by launching cannonball towards the player. Unlike the HardHead's cannonballs, however, these do not break panels. Stronger variants of this virus can withstand more damage to the shield before it raises, and can launch more cannonballs at one time, making their attacks very difficult to dodge.

IronShield
IronShield are machine cannons on four legs with two antennas. They are pink in color with a grey shield.

IronShield2
IronShield2 are machine cannons on four legs with two antennas. They are tan in color with a red shield.

IronShield3
IronShield3 are machine cannons on four legs with two antennas. They are whittish in color with a yellow shield.

Trivia

 * Interestingly, whether by coincidence or by choice of the programmers/game planners, the possible chip codes for the chips dropped by IronShield spell out "ABORT".