Guide
How the kit works
Start a fight with Preemptive Strike when you can. It attacks immediately and, upon entering battle, deals Ice DMG to one random enemy. It also has a 100% base chance to reduce all enemies' DEF by 20% for 2 turns.
Use Frost Shot for a single-target attack, or Frostbite when you want to remove a buff. Frostbite removes one buff and deals Ice DMG. If it dispels a buff, Pela's next attack deals 20% more DMG.
Use Zone Suppression to damage all enemies and apply Exposed, with a 100% base chance. At the listed skill level, Exposed reduces DEF by 40% for 2 turns. Data Collecting restores 10 Energy if an enemy is debuffed after Pela's attack, once per attack. Attack debuffed enemies to help charge the next Ultimate; Pela also deals 20% more DMG to them.
Build and why
The first set choice is four pieces of Eagle of Twilight Line. Its 2-piece Wind DMG bonus does not help Pela's Ice attacks, but the 4-piece effect advances her action by 25% after her Ultimate. For the planar slots, Broken Keel gives Effect RES and grants allies 10% CRIT DMG when Pela reaches 30% Effect RES.
If you prefer a mixed relic setup, two pieces of Messenger Traversing Hackerspace give 6% SPD, while two pieces of Guard of Wuthering Snow reduce DMG taken by 8%. Penacony, Land of the Dreams is another planar option with Energy Regeneration Rate; it also increases the DMG of other Ice allies. Lushaka, the Sunken Seas offers Energy Regeneration Rate and an ATK bonus for the first character in the lineup when Pela is not in that slot.
Use Effect Hit Rate or CRIT Rate on the body, SPD on the feet, HP Percentage or Ice DMG Boost on the sphere, and Energy Regeneration Rate on the rope. For substats, follow SPD, Effect Hit Rate, CRIT Rate, CRIT DMG and ATK Percentage in that order. Effect Hit Rate helps with her debuffs, while SPD and Energy Regeneration Rate support more frequent Ultimates.
Lies Dance on the Breeze is the top weapon choice: it gives SPD and can apply a DEF reduction to every enemy after an attack. At 170 SPD, it can also apply a second DEF reduction. Resolution Shines As Pearls of Sweat is next, with a chance to reduce the DEF of a hit enemy. Before the Tutorial Mission Starts gives Effect Hit Rate and restores Energy when Pela attacks enemies with reduced DEF.
Leveling priority
Follow the game's order: level the Ultimate first, then the Talent, Basic ATK and Skill. The Ultimate is Pela's team-wide DEF reduction, and the Talent helps her recover Energy. Basic ATK comes before Skill in this order, even though the Skill's buff removal remains useful.
For maximum ascension, you need 246,400 Credit, 50 Horn of Snow, 12 Extinguished Core, 13 Glimmering Core and 12 Squirming Core. To level all skills, the listed materials are 2,400,000 Credit, 5 Tracks of Destiny, 12 Obsidian of Dread, 54 Obsidian of Desolation, 105 Obsidian of Obsession, 12 Guardian's Lament, 28 Extinguished Core, 42 Glimmering Core and 42 Squirming Core.
Eidolons worth it
As a suggestion, Full Analysis is the most interesting Eidolon to aim for, especially with an Ice damage dealer. Pela's Skill gains a 100% base chance to reduce its target's Ice RES by 12% for 2 turns.
Victory Report is useful for Energy: Pela recovers 5 whenever an enemy is defeated. Absolute Jeopardy raises the Ultimate and Talent by 2 levels, helping the two skills at the top of the leveling order. Adamant Charge gives Pela 10% SPD for 2 turns when her Skill dispels a buff, so it depends on the enemy having a removable buff.
Common mistakes
Do not treat a 100% base chance as a guaranteed debuff. Give Pela Effect Hit Rate and check whether enemies are actually affected before relying on their reduced DEF. Keep an eye on the 2-turn duration of her Ultimate's Exposed.
Do not use the Skill solely for its dispel when the target has no removable buff. Basic ATK can still attack an already debuffed enemy and trigger the Talent's Energy recovery. Also, do not build the four-piece Messenger Traversing Hackerspace for its team SPD effect: it requires an Ultimate used on an ally, while Pela's Ultimate targets enemies.