Your Intelligence score increases by 2, and your Wisdom score increases by 1.

Mind flayer tadpoles takes over a victim's body within a week, rather than maturing at a certain age. A mind flayer typically lives up to 125 years.

Due to their strict society and typical unwavering devotion to an elder brain, illithids are almost always lawful, and their overpowering belief of other creatures being adversaries or food makes them evil. Despite this, some mind flayers are different. A mind flayer that is seperated from an elder brain for enough time might become less lawful, and a lone mind flayer that interacts with other races might grow a more friendly respect for them.

Thanks to your psionic prowess and living underground, you have developed darkvision. You can see in dim light up to 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can't discern color in darkness, only shades of gray.

As a creature of the far realms, illithids possess psionic powers. You know the Mind Blast cantrip, described below under "Mind Blast (Cantrip)". Also, starting at 3rd level, you can cast detect thoughts or levitate once per long rest. Intelligence is your spellcasting ability for these spells. Additionally, at 3rd level, you can telepathically with any creature within 30 feet of you that can understand any language.

When you grapple (see Player's Handbook page 195) an incapacitated medium or smaller humanoid, you can use your action to deal 5 (1d10) piercing damage to it. If this damage kills the target, you kill it by eating its brain. You can also use this to eat the brain of an already dead humanoid as long as its brain is still there.

Evocation Cantrip

Casting Time: 1 action                                                                                                                                                                                                                                                                                            Range: 15 feet                                                                                                                                                                                                                                                                                                              Components: V, S                                                                                                                                                                                                                                                                                                        Duration: Instantaneous

You concentrate your psionic powers into a blast in a 15-foot cone. Each creature in that area must succeed on an Intelligence saving throw or take 1d6 psychic damage. Intelligence is your spellcasting ability for this spell.