concept art for mobile game

we are looking for 2d artists to do concept art for game
games characters and assets:
-male rangers
-female ranger
-robot ranger
-alien character
-mother spaceship
-rangers' space jet
-alien's space jet
-3 pistols
-3 machine guns for rangers
-3 laser guns
-the machine gun of rangers' space jet
-the machine gun of alien's space jet
-4 armours
-boxes
-game environment
we can provide a reference to make design easier