Koops is a Koopa Troopa from Petalburg, and the second partner to join Mario's party in the game Paper Mario: The Thousand-Year Door. Very much like Kooper from the original Paper Mario, Koops can retreat into his shell
and use it as a weapon against foes, and Mario can also launch him at
switches or distant objects to hit them or retrieve them. However, he
differs from Kooper in that Mario can hold Koops' shell in place.
Koopa Paratroopas (also known as Parakoopas, Sky Troopas in Super Mario RPG: Legend of the Seven Stars, or simply Paratroopas), are Koopa Troopas
with wings. They lose their wings when they are attacked in air, such
as getting stomped or hurt by fireballs. They traditionally come in two
varieties: Red Koopa Paratroopas usually fly up and down or side to side
in a set path, while green Koopa Paratroopas often bounce in the
player's general direction. Red Koopa Paratroopas first appear in World
1-3 of Super Mario Bros., while the green ones first appear in World 2-1 of the same game. However, some Paratroopas hover left and right, but in Super Mario Bros.,
World 7-2 has left/right Paratroopas. Their name comes from
"paratrooper", a term used in the military to describe soldiers who
parachute down to attack.