Spell type

A spell type is any subtype used for the further classification of instant and sorcery cards.

Unlike creature types, spell types don't have to appear on all sorceries and instants. Instead they are only introduced for mechanical purposes.

Rules

From the glossary of the Comprehensive Rules (June 7, 2024—Modern Horizons 3)

Spell Type

A subtype that’s correlated to the instant card type and the sorcery card type. See rule 304, “Instants,” and rule 307, “Sorceries.” See rule 205.3k for the list of spell types.

From the Comprehensive Rules (June 7, 2024—Modern Horizons 3)

• 205.3k Instants and sorceries share their lists of subtypes; these subtypes are called spell types. The spell types are Adventure, Arcane, Lesson, and Trap.

List of spell types

Spell type	Variant	Year	Description
Adventure		2019	Introduced in Throne of Eldraine to represent the set's storybook and fairy tale themes. The subtype only appears on instant or sorcery spells attached to permanent cards. Creature cards are said to have "gone on an adventure" if the spell was cast first.
Arcane		2004	The subtype was first used as a major theme of Kamigawa block to represent the magic woven by the kami. Arcane spells are the main target of the Splice mechanic, and form half of the spiritcraft mechanic.
Chorus	Designed-for-digital	2023	Introduced in Alchemy: Ixalan to represent music. The subtype is used in conjunction with the intensity mechanic.
Lesson		2021	Tied to the learn mechanic introduced in Strixhaven: School of Mages. When learning you may reveal a Lesson card from outside the game and put it into your hand.
Trap	Instants only	2009	Traps have an alternative cost should specific events occur. Usually, traps have abilities that undo or punish whatever has made their alternative cost possible. The type was introduced in Zendikar block to represent the perils of the set's treasure hunting theme.