The Eternia Crystal has many different skins that players can choose. The skin can be changed in the main menu screen where the player selects a character. Each skin is purely cosmetic, and therefore does not affect the crystal's health.
The different skins are obtained by completing achievements in game and are as follows:
| Unlockable Crystal Skins | |||||
|---|---|---|---|---|---|
| Image | Name | Achievement | Image | Name | Achievement |
 |
Classic | None |  |
King's Crown | O Mighty Smiter! |
 |
Crystalline | Good Student |  |
Geode | And This Is My Weapon |
 |
Mystical | Pupil |  |
Cell | Veteran |
 |
Molecular | Brute Force |  |
Runic | From the Depths |
 |
Landscaped | To The Rooftops |  |
Waterfall | Defender of Etheria |
 |
Eastern | A Taste of Victory |  |
Western | A Challenger Approaches |
 |
Fantasy | A Matter of Perspective |  |
Urn | Perfectionist |
 |
Organic Goblet | Group Hug |  |
Book of Souls | Obedience Training |
 |
Goblet | Survivalist |  |
Skulltacular | Daredevil |
 |
Money | Master Banker |  |
Horned | Iron Man |
 |
Sky City | Mastermind |  |
Bio Container | Catch 'em All |
 |
Fusion Core | Dungeon Defender |  |
Obelisk | Team Effort |
 |
Pandora's Box | Defense is the Best Offense |  |
Lovely | Playin' Mythical Cupid |
 |
Birthday | Nightmare Anniversary Defender |  |
Trick or Treat! | Pumpkin Party Nightmare |
 |
Gobble Gobble | Nightmare Greater Turkey Hunter |  |
You Are Trendy | Legendary Defender |
 |
Ultimate | Ultimate Defender |  |
Nguzo Saba | Winter Wonderland |
 |
Ho Ho Ho | Silent Night | |||