Arcane Wasting. Characterized by the slow mental deterioration it causes, arcane wasting is a disease that infects Humanoids and spreads through spellcasting. A creature infected with this disease manifests symptoms 1d4 days after infection, which include brain fog and difficulty recalling memories. Until the disease is cured, at the end of each long rest, the infected creature must succeed on a DC 15 Constitution saving throw or its Intelligence and Wisdom scores are each reduced by 1d2. This reduction lasts until the creature finishes a long rest after the disease is cured. If the disease reduces a creature's Intelligence or Wisdom to 0, the creature dies. If the infected creature casts a spell on a Humanoid before the disease is cured, and the Humanoid is hit by the spell or fails the saving throw, that Humanoid must succeed on a DC 15 Constitution saving throw or also become infected with the arcane wasting disease.

Magic Resistance. The white ape has advantage on saving throws against spells and other magical effects.

Spellcasting Animosity. If the white ape sees a creature cast a spell, the ape has advantage on attack rolls against that creature on the ape's next turn.