At long last, below is the 20th level class feature, Eldritch Mastery. With this article, we have a complete Starfinder Roleplaying Game version of the OGL warlock from 5e.

Here’s the index of where to find elements of the class:

Class table and proficiencies
Spell access and spell slots
The Fiendish patron
Fiendish patron gifts
Invocations
Pact Boons — Pact of Armor and Pact of the Vessel more pact boons here.
— Pact of Alteration and Pact of Change
Rules for Archetypes and NPCs

Eldritch Master
At 20th level, you gain the ability to cast spells as a mystic, technomancer, or witchwarper (your choice) of 13th level (gaining spells known and spells per day as a 13th level character of the selected class, with a caster level of 13 for these spells). Once this choice is made, it cannot be changed. You cannot cast any spell that requires you to have a class feature you lack.

Additionally, you can select any one patron gift from any patron that does not list a level requirement, or any patron gift from your own patron.

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