Spellcasting: At each level, a savant aboleth gains new spells per day as if it had also gained a level in an arcane spellcasting class it belonged to before adding the prestige class. It does not, however, gain any other benefit a character of that class would have gained, except for an increased effective level of spellcasting. If an aboleth had more than one arcane spellcasting class before becoming a savant, it must decide to which class it adds the new level for the purpose of determining spells per day.

Glyph Mastery (Sp): At 1st level, a savant aboleth has mastered the ancient craft of the aboleth glyph. When a savant aboleth creates an aboleth glyph, multiply the base cost of the glyph by 75% to determine its cost in XP and raw materials.

Additionally, a savant aboleth gains the ability to cast glyph of warding as a spell-like ability a number of times each day equal to its savant aboleth level. Each use of this spell-like ability costs 200 gp in raw materials (rare inks, crushed shells, and powdered gemstones). Alternatively, a savant aboleth can expend 8 XP instead of spending the 200 gp.

Although this ability mimics a divine spell, this spell-like ability uses arcane magic.

Ossification (Ex): As a savant aboleth grows more powerful, its body begins to transform and become more heavily armored. Ridges of bone form atop its skull and run down its spine, eventually encasing the savant aboleth's brain and back in thick natural armor. A savant aboleth's natural armor bonus improves by 2 points at 1st level, 3rd level, and 5th level.

Enlarged Enslave (Su): Beginning at 2nd level, the range of a savant aboleth's enslave special attack is doubled from 30 feet to 60 feet.

Recrudescent Memories (Ex): At 2nd level, a savant aboleth's memories surface in a sudden blast of forgotten and hidden knowledge. The memories quickly return to the hidden depths of the aboleth's mind, but the flash of insight is enough to infuse the creature's mind with a powerful rush of inspiration and spontaneous evolution. The aboleth can increase its Intelligence, Wisdom, or Charisma score by 2 points. This is a permanent, untyped bonus, similar to those gained by advancing four character levels.

At 4th level, a savant aboleth's memories flare again, and it can increase its Intelligence, Wisdom, or Charisma score by 2 points.

Greater Glyph (Sp): Starting at 3rd level, a savant aboleth's glyph of warding spell-like ability improves and becomes a greater glyph of warding spell-like ability. It must expend raw materials worth 400 gp (or 16 XP) each time it uses this spell-like ability. A savant aboleth can voluntarily underpower this spell-like ability to cast a glyph of warding instead.

True Enslave (Su): Beginning at 4th level, a savant aboleth's enslave ability grows much more powerful. An enslaved creature can no longer make a new Will saving throw each day to break free from the enslavement; the condition is permanent until successfully dispelled. Additionally, the enslavement lasts no matter how far the savant aboleth moves from its slave.Slaves on a different plane remain enslaved, but the savant aboleth cannot communicate with them telepathically until they return to the same plane.

Elder Glyph (Sp): At 5th level, a savant aboleth's greater glyph of warding spell-like ability improves and becomes an elder glyph of warding spell-like ability (see below). It must expend raw materials worth 1,000 gp (or 40 XP) each time it uses this spell-like ability. A savant aboleth can voluntarily underpower this spell-like ability to duplicate either a glyph of warding or a greater glyph of warding instead.