
The standard-tier ATK rune, Rare rarity: base stat ATK +16 at 30 CP for 2 energy. One of the four tiers of the ATK rune line for carried items.
ATK Rune
Rare · ATK +16

Database · Runes · ATK line
The standard-tier ATK rune, Rare rarity: base stat ATK +16 at 30 CP for 2 energy. One of the four tiers of the ATK rune line for carried items.
Rare · Standard tier · ATK stat line
Source
Rift System · Holo-Battle Sim
Source
Rune Crafting
Source
Adventure Rank · Chest

The standard-tier ATK rune, Rare rarity: base stat ATK +16 at 30 CP for 2 energy. One of the four tiers of the ATK rune line for carried items.
Rare · ATK +16
The game's item data lists 3 sources for the ATK Rune: Rift System · Holo-Battle Sim, Rune Crafting, Adventure Rank · Chest. The Holo-Battle Sim rift is the recurring farm for every rune tier.
It grants ATK +16 as its base stat, weighs 30 CP and costs 2 energy to socket. It is the standard tier of the ATK line, whose four tiers run Common (Uncommon), standard (Rare), Advanced (Epic) and Premium (Legendary).
No published build on this site recommends the ATK line yet; the recommended-build panels on the Aniidex pages will pick it up as soon as one does.