What the effects react to
Shards
Shard entities react to shards being generated during the fight, turning generation into damage, healing or stats. 13 relics and items are built on it: 13 relics and 0 items.
Updated for patch 0.5.10
Generated and banked
Shard effects read one of two counters. Shards generated this game only ever rise: Shard Energy Velocitizer gives 1 Attack Speed per 5 of them, and Magician's Ledger 1 Magic per 8. The bank is what you are holding, and every purchase drains it: heroes are priced 15 to 45 Shards by rank, items 5 to 25, relics 10 to 40. Shard Precision Prism and the Assassin upgrade Banked Presence both read the bank, and Crit Rush Assassins runs the two together.
Shard Maximizer sits between the two. At the end of each combat it pays 1 Shard per 5 in the bank, capped at 20, and its text keeps that interest out of generation, so it raises the bank without moving the Velocitizer. Since 0.5.7 it also counts Shards generated during the fight.
Damage and Shields on arrival
Shard Fluctuator deals 500 damage to all enemies whenever Shards are generated, Shard Power Extractor 10% of each enemy's Max HP with a 2,500 floor, and Shard Resonator gives heroes 400 Shields. Generation Conduit adds 15 Crit and 500 Shields on the same trigger once 25 Shards have been generated. All of them want Shards arriving mid-fight: the Assassin upgrade Shard Collector yields one on every other Crit, the Duelist upgrade Golden Eye one every 9 auto attacks. Shard Lattice and Shard Extractor pay 3 and 6 on combat victory, once the fight is already won, which is late for relics that turn a Shard gain into damage.
Resonator and Greedy cuts
Both Shard builds have dropped from S to A. Shard Gen Assassins carries five relics: Resonator, Fluctuator, Power Extractor, Generation Conduit and Shard Ascendancy, which generates one more Shard whenever Shards are generated. Dragomir and Hoyoung both take Shard Collector, and Hoyoung holds Greedy Shiv. Rush Shard Gen Duelists adds the same five to the Rush Duelists relics. Shard Resonator fell from 1,000 Shields to 600 in 0.5.3 and to 400 in 0.5.5, which cost the Duelist version its S; the Assassin version also took the 0.5.4 cuts to Greedy Shiv, 750 damage to 450, and Greedy Gauntlet, 1,250 Shields to 750.
Relics and items that scale with Shards
Shard FluctuatorUniqueOn Shards generated, deal 500 damage to all enemies.
Shard ResonatorUniqueOn Shards generated, Heroes gain 400 Shields.
Shard AccumulatorUniqueQuest: Generate 20 Shards. Rewards: At start of combat, gain 2 Shards.
Shard LatticeCommonOn combat victory, gain 3 Shards.
Shard VesselCommonQuest: Generate 15 Shards. Rewards: Heroes gain 20 Crit and 5 Omnivamp.
Shard ExtractorRareOn combat victory, gain 6 Shards.
Shard ConstructorRareAfter Stall (30), gain 9 Shards.
Shard MaximizerUniqueGain interest on saved Shards. At the end each combat, gain 1 additional Shard per 5 Shards in your bank (Max: 20. Does not count towards generation).
Shard AscendancyEpicQuest: Generate 25 Shards. Rewards: On Shards generated, generate 1 more Shard.
Shard Precision PrismEpicHeroes gain Crit equal to the number of Shards in bank (Max: 1000).
Shard Energy VelocitizerEpicHeroes gain 1 Attack Speed per 5 Shards you've generated this game.
Shard Power ExtractorLegendaryOn Shards generated, deal damage to all enemies equal to 10% of their Max HP (Minimum: 2500 damage).
Shard PouchUniqueGain 12 Shards.