Obtain: Extra Stage 4, "Yes! Nice-Bodied!", unlock by passing "The Nice-Bodied Appears!? bill.
Etna is a character designed around HP, DEF, HIT, and ATK. This statistical build is reflected in her Weapon Fortes: Spear, Axe and Gun. Her stats are best-alligned with the Spear weapon; as it plays to her's strengths.
While she can use Guns, her HIT-SPD ratio will reduce her damage output if not customized while her Axe Forte meanwhile only allows her to learn up to the third Tier of skills, prompting Chara World customization in order to be effective.
Etna's native Evility "Dominant Smile" increases the stats of allied Prinnies dispatched by 30%. This is handy if the player uses the Prinny class heavily; though is unimpressive on it's own. The remainder of her Evilities are rather situational. Sadistic however, can be a excellent Evility as it allows Etna to deal 30% extra damage to enemies with full HP and all enemies will initially have 100% HP if they are not damaged by anything else.
Etna is lackluster when she first joins the party, (Due to unimpressive starting Aptitudes) but subsequent Reincarnations transform her into an excellent back-up character. She can also learn all Spear skills up to Meteor Shower by the Evility Shop.