The Grub-Dogs, Amphitubers, Snavians, and other types of monsters are the main antagonists of the Pikmin video-game series, being indigenous life-forms that reside in planets inhabited mainly by the Pikmin, and are organized by families (although some do not have a known family, they may be related in some way).
They are encountered mainly in the surface and underground caves on PNF-404, but can also be found on the planet featured in the video-game Hey! Pikmin, a spinoff of the series.
Defeating hostile species constitutes a major part of gameplay in all Pikmin games.
Despite the majority's motivations (eat or kill Pikmin) are out of pure predatory instincts rather than true evil, some of them can be considered as true villains because of their behavior, because they appear to display human-level sapience and also because some of them do not attack for feeding like a true predator; much like the Puffstool (who turns Pikmin into Mushroom Pikmin to turn them against the player and other Pikmin), the Burrowing Snagret (who appears as an Assist Trophy in Super Smash Bros. Ultimate), the Empress Bulblax (whose motivations are similar to the Queen Metroid from the Metroid series, by giving birth to Bulborb Larvae and use them against the player, and also attacking by herself), the Segmented Crawbster (whose motivations are similar to Rollodillo from Super Mario Galaxy 2), the Smoky Progg, the Careening Dirigibugs, the Man-at-Legs, the Waterwraith, the Titan Dweevil, the Plasm Wraith, the Armurk and the Leech Hydroe (those who want to kill the Pikmin and their leaders for being evil, or brainwashed in Leech Hydroe's case).
For the most part, every enemy is its own entity, interacting only with the Pikmin and leaders. However, some enemies have passive or active interactions with the environment, other enemies, or miscellaneous objects.
- In Pikmin 3, most enemies will be unable to detect Pikmin and leaders if they are hiding under tall plants.
- In Pikmin 2, if an Emperor Bulblax gets close to a bomb-rock, it will eat it without needing to be coaxed into doing so.
- The fire on a Fiery Bulblax or a Pyroclasmic Slooch's back will be put out should it go into water. Both creatures reignite once they leave the water.
- If a member of the Mandiblard family touches water, it will steadily lose health, and if it is near a wooden bridge and not in pursuit, it will begin deconstructing it.
- Wogpoles and Puckering Blinnows will start flailing around if they're on dry land, but they are able to swim freely if they're underwater.
Some creatures keep a bond with others. To maximize the chances of survival, some enemies can be seen next to others, normally of their own species, and oftentimes interacting with them when a fight for survival is taking place. Dwarf Red Bulborbs, Dwarf Bulbears, etc. are often found next to larger enemies of the same species or of the species they are mimicking. When under attack in Pikmin, they may scream in order to wake up their larger allies.
Other creatures choose to follow a leader, normally of their own family. An example is the Bulbmin, who lose all sense of control should their leader perish, the Scornets, who obey the command of the Scornet Maestro, and the Shearwig, which can be found under the control of the Queen Shearwig, and are otherwise independent.
Hostility between enemies is non-existent, but cases of enemies damaging each other are not. Some enemies may, if inadvertently, hurt others. This normally happens when they try to kill Pikmin or leaders. Not many enemy attacks are made to hurt others, but the following are:
- The Empress Bulblax can kill her young by rolling into them.
- A Gatling Groink can damage other enemies with its shots (including other Groinks), but not itself.
- Most lithopods with boulders can harm other enemies or even the launcher itself.
- The Beady Long Legs, Raging Long Legs, and Baldy Long Legs can stomp on and kill other enemies, particularly on the Angle Maze and Tropical Forest, respectively.
- In Pikmin 3, Yellow Wollywogs can kill or injure other enemies if they land on them.
- In Pikmin 3, Skutterchucks can harm and kill other enemies if their crystal nodules land on them. They can even kill themselves.
- The Man-at-Legs can hurt other enemies with his gun. This is impossible to see without hacks, since the creature never appears alongside other enemies.
Although most do not have specific gender, some do seem to have:
- Emperor Bulblax (male, for having the word "Emperor" in his name)
- Empress Bulblax (female, for having the word "Empress" in her name and for giving birth to larvae)
- Man-at-Legs (male, for having the word "Man" in his name)
- Waterwraith (male, for the sounds it emites and for his scientific name "Amphibio sapiens")
- Segmented Crawbster (male, according to a Youtube user)
- Raging Long Legs (female, for releasing Mitites upon her defeat)
- Titan Dweevil (male, according to the Spanish Pikmin wiki)
- Scornet Maestro (male, for having the word "Maestro" in his name and for having mustaches)
- Armurk (male, according to the Spanish version of Hey! Pikmin)
- Queen Shearwig (female, for having the word "Queen" in her name)
- Luring Slurker (male, according to the Spanish version of Hey! Pikmin)
- Some of them, like the Wogpole or the Skitterleaf, are harmless for the Pikmin, but not for the captains (because when shaking Pikmin off, they can damage the captains if they are near).
- The Scornet Maestro and the Queen Shearwig are true evil because they appear to display human-level sapience when they command their minions to attack, when the Scornet Maestro becomes frustrated when his Scornet army's attacks fail, and when the Queen Shearwig shrieks excitedly when Olimar become vulnerable to her One Hit K.O. attack.