Complete Soul Cores and Soul Resonance

Three sources

• Forging: costs that boss's shards, tokens and kill marks, with amounts scaling by the boss's level; capped at two cores per account per week across all bosses, and the forged core is account-bound.
• Chests: every world-boss chest has a 0.08% chance to drop one directly, with the odds published in game.
• Server auction: SSS auctions sell fully disclosed cores; won cores can be resold once through the official market.

Socketing and reveals

Socketing reveals three things: random potentials, a fixed passive and the Soul Burst skill. Socketing a new core into the same weapon overwrites the old one, which is destroyed. Auction cores are fully revealed before bidding, so what you see is what you buy.

Soul Resonance

Each boss has its own account-wide Soul Resonance track running from stage 0 to 50, and the five lines are independent. Regular stages consume that boss's shards, priced at exactly one chest's guaranteed shard drop; stages 5, 10 and every fifth stage up to 50 each require one complete core, and every stage also costs gold that scales with the boss tier and target stage. Each stage permanently raises account ATK and MATK by a percentage, applied from character Lv 150, at a flat rate per stage. A maxed line gives +4% to +8% depending on the boss tier, and all five maxed total +30% ATK and +30% MATK. The socketed core's own effect still grows only on those core stages, reaching +30% at the top.