Creatures in Impossible creatures fall under the following broad classifications below.
Creatures that can only attack when touching their target. They normally have high damage and some useful abilities and are the hard counter to artillery, since artillery end up attacking themselves when the melee close the distance.
Creatures that are capable of attacking from a distance. These creatures have to stay away from melee creatures. Ranged creatures are the hard counter for melee but are very vulnerable to artillery.
Creatures that are capable of attacking from a distance and have a splash damage which damages all units within the target zone. They are the hard counter to range.
Creatures like Camasps, usually weak, low stats, cheap with assassination. Their only purpose is to counter Loners. Usually these creatures, when sent into battles, are not expected to return.
Meatshields are incredibly hard to kill, but their damage is very low. They can be ignored when not combined with other troops, but with a strong ranged support unit they form a wall blocking access to the damage dealing unit.
They are generally cheap, and easy to spam. Examples include walking turtles, shield bugs, etc.
A creature specialized to kill labs very quickly. The most potent are woodpecker combinations (especially those with frenzy), like Woodpecker vultures and Woodpecker Mantises.
Creatures with the loner ability fall under this group. They are superbly suited to kill expansions and henchmen on their own, and make great raiders. Examples include Panther lobsters.
Spam / Cheap 'n NastyEdit
Creatures that are cheap for their level, these creatures are incredibly cost-effective and on a cost-to-cost basis can beat powerful units easily. Examples include Frownodon Barracudas, which can easily beat much more powerful melee like Moosobsters if both groups of creatures are purchased from the same pool of resources and in numbers significantly above 4.
Spam is generally better cost-effectively due to the "doggie effect," which states that the power of a group of creatures together equals n(n+1)/2 creatures fighting one by one, where n = number of creatures in the group.
Creatures that do not attack in battle, but come with an useful set of abilities, like Web Throw, Flash, Defile Land, etc.
Creatures designed to sneak in and take out expansions and henchmen, such as Horse rattlers.
Flyers which are extremely cheap, deal incredible damage ( over 100 / sec is easily reached with modifiers like frenzy ) and use the inherent mobility and speed of flyers to apply this terrific damage to quickly kill a group are called glass cannon flyers. They are extremely vulnerable to sonic but are otherwise very deadly, examples include Shark Ravens.
These flyers are quite durable and can go toe-to-toe with weak sonic units in groups.They have good damage but are generally not good labrushers. Horned specimens of this group are the most effective counter to the Super Tank Flyers. Examples include the Mooseraven.
Super Tank Flyers : Incredibly high defense flyers may be classified as Super Tank Flyers. With very, very high effective hit points, these flyers can often take on sonic units of equal strength and number and win. They can usually slaughter any creature lacking horns, and take on massed AAs. Horns and quills are their only true counter, with horned tankish flyers like mooseravens being the best. Examples include the condorturtle, the only viable Super Tank Flyer which far outperforms other specimens. It is followed by the vulture turtle far behind.