Every Buddhist has to defeat ego, on his or her way to Liberation & Enlightenment.
It's said by many wise that defeating oneself is far greater victory than defeating countless enemies.
Enlightened Mind can perceive it's own pure nature, without delusions, without mind's veils, without stiff ideas and without feeling of separation introduced by ego.
Without personal ego beings are Liberated, there's no personality that can be hurt, there's no mental barrier of separation between one and rest of beings.
Liberation is a state of mind in which all suffering and the causes of suffering are completely overcome.
Liberation happens through dissolving the false idea of presumed 'I'.
Once Liberated, mind's disturbing emotions fall away.
When the last stiff concepts are let go as well, then one becomes Enlightened.
Ignorance, confusion and delusions, as well as stiff ideas, as well as disturbing feelings & thoughts, are mind's veils to be purified before mind can perceive itself perfectly, before mind can be enlightened.
Unenlightened mind often thinks it's body itself and that's all that's real.
Unenlightened mind perceives world through it's bodily senses and through brain, it feels separate from others because of personal ego. Unenlightened mind's perceptions are impure, world's perceptions are distorted by various mind's veils - are delusional.
Enlightened One knows that he or she is Mind, and has impermanent body. This Mind lacks ego so it's both that it's nature as well as that it's perceptions are pure as well as perfect, there's no suffering or other hindrances in the Enlightened One.