Opposition Schools

The wizard subclasses in the Player’s Core Rulebook concentrate the character’s power on a single school of magic, what some earlier editions called school specialization. All arcane magic comes from the same or a similar arcane force, but those who embrace and control magic through study and training are granted greater access to the magic they study than any other class. In fifth edition, the secrets of that arcane art are deliberately vague to allow game masters to interpret those secrets for themselves.
In prior editions, however, the laws of magic were a bit more codified, including how the different schools of magic interact. In some ways, this aligned with the four primal elements, where each element has one in direct opposition: fire and water oppose each other, as do earth and air.
Applying a similar concept to the schools of magic resulted in the law of Schools of Opposition. These opposition schools limited the wizard’s power and enhanced their capabilities in their core school. This prevented a wizard from learning spells from their opposition school and granted them greater power in their school of specialization. The fifth edition subclasses enhance their power in the chosen school, but without limitations. Using this system, the chart above shows each school of magic and its fundamental opposition, based on the concepts provided in earlier editions of the game.

Illusion and necromancy represent the ephemeral and physical, transmutation and abjuration represent manipulation of primal forces and the stability of those forces, divination and conjuration represent understanding the world and its nature and understanding the cosmology beyond the world, and evocation represents drawing power from without while enchantment harness the power within.
The following rules adapt the older opposition spell rules, providing limitations and further enhancements to the wizard’s school of choice, though with fewer restrictions than the earlier editions to remain in line with the fifth edition design philosophy. These limitations and enhancements are as follows. The terms “specialist” and “specialist wizard” will represent any wizard utilizing a subclass from the Player’s Core Rulebook.