Eternity's build in centers around losing HP with each of her powerful attacks. While it may seem counterproductive to claim a DPS who constantly loses HP is one of the best DPS units in the game, Eternity has a variety of passives that make her shockingly hard to kill.
At Insight One, Eternity is immune to Blood, Poison, and Corrode statuses. At the start of a round, she gets a stack of Blood of Longevity, boosting her DMG Dealt and DMG Heal. This immunity, along with her debuff Incantation and steady DMG potential, makes her an excellent match for teams with steady healers, weak enemy bonuses, and debuff perks.
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Since Eternity is a main DPS in, she will often be the one to deal with the killing blow against enemies. As such, Hopscotch fits into her kit well, building up to an explosive and beneficial Ultimate. If Hopscotch gets to Level 60, it gives Eternity an 18% Incantation Might bonus. Meanwhile, for each enemy Eternity manages to defeat, she will get one stack of up to +8% Ultimate Might. She can get up to four stacks at any one time. This improves the DMG Dealt by Odd Story in Exeter and boosts her Leech Rate.
Because Eternity has a lot of resources to make up for the HP drain in her Incantations, it's better to support her DMG output. As comes out with more Psychubes, look for Psychubes that support Eternity's Ultimate, Odd Story In Exeter.
If you want more Ultimate Might faster, Brave New World won't be wasted on Eternity. This Psychube has an 18% Ultimate Might bonus for further DMG and Leech Rate potential. Once Eternity utilizes this bonus, the next Incantation gets up to 40% more Incantation Might. Antique Fan is the better Incantation to use
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