Dryad's Blessing and Dryad's Bane are the buff and debuff inflicted by the Dryad NPC's Dryad Ward. Rather than directly attacking nearby enemies, the Dryad casts the Dryad's Ward while enemies are nearby, which summons two circles of leaves, with the outer circle indicating the range of the attack. When in the range of the Dryad's Ward, all players and NPCs gain the Dryad's Blessing buff, while all enemies with a clear line of sight to Dryad are inflicted with the Dryad's Bane debuff.
Counting from when the circles of leaves are summoned, within the first 1.67 seconds, the radius of the Dryad's Ward is 18.75 tiles (300 pixels). The radius then generally increases to 37.5 tiles (600 pixels) over the course of 3.33 seconds, and remains unchanged for another 3.33 seconds, after which the radius generally increases to 75 tiles (1200 pixels) over the course of 1.17 seconds, then the Dryad's Ward dissipates. 0.5 seconds after the circles of leaves are summoned, the buff and debuff are continuously inflicted on entities within the radius of the circle of leaves.[1]
The Dryad's Blessing provides the following effects:
Visual effect: Green sparkle trail from feet while moving
The Dryad's Bane debuff deals 4 damage per second to enemies. This debuff deals additional damage based on players' progression through the current world. Additionally, the total progression boost is multiplied by a game mode-specific multiplier. See NPC stat boosts for the specific details of these boosts. For example, if the current progression boost is +40% total and the world is in Expert Mode, the Dryad's Bane damage is actually raised by (1.4 × 1.5) = 2.1 = +110%. The final damage rate is rounded down, so e.g. 4 damage per second × 2.1 = 8.4, rounded down to 8.[6]
With no bosses defeated, the total damage rate is 4 / 6 / 7 DPS.
With all bosses defeated, the total damage rate is 10 / 16 / 18 DPS.
↑Information taken from the Desktop1.4.4.9 source code, method AI_111_DryadsWard() in Terraria.Projectile.cs.
↑Information taken from the Desktop1.4.4.9 source code, method AI_007_TownEntities() in Terraria.NPC.cs.
↑Information taken from the Desktop1.4.4.9 source code, method BeHurtByOtherNPC() in Terraria.NPC.cs.
↑Information taken from the Desktop1.4.4.9 source code, methods UpdateBuffs() in Terraria.Player.cs and Update_NPCCollision() in Terraria.Player.cs.
↑NPCs' health regeneration is much simpler than player's health regeneration: town NPCs have a single regen counter which increases every tick (i.e. increases 60 times per second) while the NPC is not at max health; once the counter reaches or passes 180, the NPC gains 1 health and the counter resets to zero. The rate at which the counter increases is 1 per tick normally, or 11 per tick with Dryad's Blessing. Information taken from the Desktop1.4.4.9 source code, method CheckLifeRegen() in Terraria.NPC.cs.
↑Information taken from the Desktop1.4.4.9 source code, method UpdateNPC_BuffApplyDOTs() in Terraria.NPC.cs.