By consuming the Essence of Endless Lives, the primal urge to experience life in all of its infinite variety, you ensure that your soul will have as many chances to experience life as you wish.
*Your soul is unbound from the normal cycle of existence and becomes absolutely indestructible, untrappable, and unownable. Nothing short of the Supreme Being can prevent you from being reborn.
*Every time your life ends, by any cause up to and including total conceptual retroactive destruction of your existence, you will reincarnate into any universe you wish and at a location and time of your choosing. With one exception, every time you are reborn will be into a separate timeline.
*The exception is that you may choose to 'rewind' the same life you just died in, all the way back to the beginning. You may rewind more than once. You rewind all the way back to birth every time you choose to rewind at all. You do not have to rewind any life unless you want to, but after you have moved on to a new life you may not go back and rewind a prior life yet again.
*As part of your being unbound from the normal cycle of existence you may choose the parents you are born to and the circumstances you are born into, each as privileged or as poor as you want them to be. However, from birth onward your karma will be neutral and without any predestined fate or destiny.
*You may reincarnate into a newborn of any sentient race that exists in-setting, and will for the duration of that lifetime have all the powers and abilities that your new body would normally have. You may reincarnate into any entity below the 'cosmic being' tier of power.
*You may, if you wish, have your memories and abilities lie 'dormant' until you are out of infancy and into childhood.
*You may choose to reincarnate into a 'special' example of your new race, one born with or destined to obtain powers or abilities not common among its species, but only so long as such entities would already exist in-setting to potentially reincarnate to. (For example, you could not reincarnate into a baby with mutant superpowers unless superpowered mutants were already a thing in that world.)
*You may freely reset your physical stats with every new life, within the racial minimums and maximums of the new life you are reincarnating into. Your mental stats will remain your own but you will carry forward any improvements in those stats between lives. You will never have 'dump stats' unless you choose to, and 'dump stats' will always reset to normal after you end a life.
*With each new life you will have the opportunity to 'leave behind' any emotional or mental trauma that occurred in previous lives and start afresh, if you choose to.
*You gain perfect memory with infinite storage. You always have perfect awareness of which memory occurred in which lifetime.
*You are always naturally adapted to whatever new form you reincarnate to however weird or non-humanoid it may be. Any species you are born into will be experienced as if you had always been that species. In later lives the memories of these more exotic existences will remain comprehensible, if possibly somewhat detached from your current existence.
*Barring another ability or Essence that would allow them to, powers and abilities do not transfer between lives unless they would be an artifact of the soul or the mind and not the body. Likewise, powers and abilities only transfer between lives if the metaphysics of the universe you are reincarnating into would support their existing there.
*As a specific exception to the above, note that "muscle memory" is actually part of the mind and so mundane skills and knowledge - even physical skills - always carries over. Your perfect memory will keep you from suffering from inconvenient reflexes or habits that may be associated with a body shape that you no longer have.
*You may end your endless cycle of lives and move on to what comes next, but only if you while entirely in your right mind and with the utmost sincerity want to.