Spellcraft Specialization (5e Feat)
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Prerequisites: The Ability to cast spells using spellslots
Choose two schools of magic. One you will lose access to, and can no longer take spells from. If a feature or ability would allow you to take a spell from that school, you can instead replace it with another spell of the same level of any spell list. The other school you are considered to have expertise for (Double the proficiency bonus to Spell Save DC's and Spell Attack Rolls), and if the spell allows you to grant healing, or deal damage, or otherwise roll dice, you may roll, adding your proficiency modifier if you so choose.
In addition, you can choose a Class with the ability to cast spells or use Psionics. You count as a caster of that class, using the spell slots of any class you actually have that can cast spells, or gaining Psi Points for use with that class's features respectively. For example if you are a Wizard, and taking this feat for Druid, you can cast Druid spells with your Wizard spell slots using Intelligence in place of Wisdom, or vice versa. When you gain spells from your class, you may learn spells from that class if that class normally has to learn spells. You may prepare twice as many spells as normal. This works retroactively, and you may learn, and prepare spells from earlier levels as if you had this feat from level 1 when you gain this feat.
You gain an archetype from that class, and any abilities of the class that that archetype requires to function correctly, in addition to one other feature from the class of choice (The feature must be at, or below your level when you take this feat, but can later be retrained to take a different feature) For example, if you took Cleric you would gain Channel Divinity from the Cleric because all the Archetypes require it. In addition, you could take the Destory Undead feature if you are at least 5th level. If you took Circle of the Moon Druid, you would gain Wild Shape because the archetype requires it, and you could also take Druidic, retraining it to Timeless Body once you are Character Level 18. Features that refer to the level the class is instead refer to the level of the class you took this feat through. For example, if a feature referred to your Druid level, and you took this feat as a Wizard 4/Fighter 1, the feature would use your Wizard level, assuming you got the feat at Wizard 4. If you gain this feat through an alternative method (Such as Human,Variant), it defaults to the class that gave you the ability to cast a spell.
This feat can be taken multiple times, each time you take it you must lose access to a new school of magic, and gain expertise in another one.