Shroids are gray Shroob robots with yellow spots and green photoreceptors. They appear in the game Mario & Luigi: Partners in Time, and they are found in Toad Town. Shroid's name is a portmanteau of "Shroob" and "android".
In battle, Shroids use a variety of attacks; first, a Shroid can trap Mario and Luigi in crystals while charging up an energy blast in its arm cannon. The brothers can break these crystal prisons by constantly jumping. After breaking the crystals, one of the brothers has to jump over the charged energy blast after the Shroid stops to fire it. The brother it shoots at can be predetermined by looking at who it first traps in a crystal.
A Shroid can also summon a Shroob UFO to bring a Spiked Ball to the battlefield. This spiked ball either has a red "M" or a green "L" printed on it, indicating which Mario Bro. the weapon will be used against. The Shroob UFO drops the spiked ball on top of the Shroid. It then throws the spiked ball at the appropriate Mario Bro. This spiked ball can be deflected with a hammer strike from one of the Baby Mario Bros. The weapon then bounces back and hits the Shroid, damaging it and causing it to malfunction if it still has HP left, which means all future attacks will be reversed (an attack that should normally hit Mario will hit Luigi instead, or vice versa). This attack can cause the dizzy status if not countered properly.
The Shroid's last technique is less of an attack and more of a test of the Mario Bros.' skill; it holds up a series of flags: either a red flag, a green flag or both flags each time. Depending on what color the flag is, the corresponding Mario Bro. has to quickly jump (if the Shroid holds up both flags, both Mario Bros. have to immediately jump). The Shroid repeats this process from two to six times. If the brothers mess up (either by missing a jump or by having the wrong brother jump), the Shroid throws both flags at the Mario Bros. The flag-throw cannot be dodged. If done correctly, the Shroid will not attack. A very rare thing is that the flags can be jumped on. Sometimes, the Shroid attempts to fake out the brothers, causing them to jump prematurely (and thus be damaged).
Mecha-Chomps from Mario & Luigi: Superstar Saga and Mechakoopas in Mario & Luigi: Superstar Saga + Bowser's Minions, Mario & Luigi: Dream Team and Mario & Luigi: Paper Jam malfunction in a way similar to a Shroid and are battled in a very similar way.
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