Occultist - Debuffs, Pets, and Acid/Vitality Magic

What It Does Well

Officially described as a craft centered on summoning and powers borrowed from the three witch gods Bysmiel, Solael, and Dreeg, using abhorrent curses and spells that damage with poison, acid, and entropic energy.

• ▸Debuffs: the Curse of Frailty tree applies sustained area resistance reduction covering physical and elemental on top of its own damage types, so it stays useful in any build.
• ▸Pets: two controllable pet-bonus pets, with pet skills occupying a large share of the tree - pet builds are close to self-sufficient on this mastery alone.
• ▸Personal damage: most damage comes as mixed types, so narrowing to one type or unifying with damage conversion makes scaling far easier (see the Damage Conversion article).
• ▸Flat damage: through its buffs, Occultist supplies among the highest flat damage that can ride on weapon attacks of any mastery.
• ▸Defense: percentage absorption of total incoming damage, 100% skill disruption protection, resistances to physical, vitality, chaos, acid, and elemental, Defensive Ability, and both a percentage instant heal and flat health regeneration.
• ▸Aspect of the Guardian in particular supplies physical resistance - which is important yet hard to get from gear - alongside enough acid resistance to stop worrying about it.

Strengths and Weaknesses

• ▸Strength: steady play through damage over time and sustained skills, plus very strong debuffs for resistance reduction, slows, and Offensive/Defensive Ability reduction.
• ▸Strength: strong support for allies and pets, making it one of the masteries that can carry a pet-bonus pet build.
• ▸Strength: supplies large amounts of flat damage for weapon attacks, and has good hosts for devotion procs.
• ▸Weakness: burst damage requires pairing with a mastery that has strong weapon-attack skills.
• ▸Weakness: low Physique and health growth.
• ▸Weakness: Defensive Ability is hard to secure and health is low, so without deliberate defensive investment a critical hit can kill outright.

Choosing a Partner and Getting Started

Occultist is on the partner-agnostic side of the roster - it contributes to almost any pairing. That means you can choose the partner purely by what you want covered.

• ▸Shaman: the standout pet pairing in the base game - the two masteries' buffs reinforce the pets while keeping the character itself durable.
• ▸Soldier: brings weapon-attack skills and durability, converting Occultist's abundant flat damage into burst through weapon hits.
• ▸Nightblade: adds dual-wield damage and mobility, with acid and bleed overlapping Occultist's own damage types.
• ▸Trying to scale both pets and yourself tends to stall after the midgame - decide early which side to favor and adjust at the Spirit Guide (see the Respec article).
• ▸For how pet scaling works (player-bonus versus pet-bonus), see the Pet and Player Bonuses article.

1. Official Grim Dawn Game Guide: Masteries — Confirms the official description of Occultist as focused on summoning and powers borrowed from the three witch gods, using curses and spells that damage with poison, acid, and entropic energy.
2. Grim Dawn Japanese Wiki: Occultist — Confirms the two pet-bonus pets and the acid/vitality/chaos/bleed focus; Curse of Frailty reducing a wide band of resistances including physical and elemental; the difficulty of scaling both pets and character with specialization being more stable past the midgame; the highest flat damage supply of any mastery; Aspect of the Guardian covering physical and acid resistance together; the especially strong base-game pet synergy with Shaman; and the listed strengths and weaknesses.
3. Grim Dawn Japanese Wiki: Masteries index — Confirms the attribute growth (Physique 1.5 / Cunning 2 / Spirit 3.5), favored damage types (1. acid and vitality, 2. chaos, 3. bleed), and the positioning as a caster strong at debuffs, damage over time, pets, and supporting other masteries.
4. Official Crate Forum: Grim Dawn Version v1.3.0.4 + Hotfixes — Official patch notes for the verified version.