Dúnmharú - Alien monster based upon Japanese serpentine dragon designs with a more bat-like appearance. Done in Adobe Photoshop using opacities for shading.
Innealtóir - Alien design based upon a humanoid insect. Done in Adobe Photoshop using opacities for shading and the wings in Adobe Illustrator using a Live Trace of dragonfly wings.
Riuil - Alien design based upon amphibious creatures. Biolumiescent spots on the skin allow the alien to see underwater. Made in Adobe Photoshop using opacities for shading and layer effects for glowing spots.
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Alien Concept Art

Concept designs for various alien cultures based upon animal characteristics.