When you attempt to revive someone either by an item, spell or other magical effect, you roll a d100 on the table. You add or subtract any relevant modifiers.

Revivify Table

d100 minus 5 times the # of previous deaths.Effect
1-5Your souls is brought back, but possessed by another creature. Your character becomes an NPC controlled by the GM.Sometimes fate has a cruel sense of humor.
6-9
You are dead.Death catches up to us all
10-15You always have 1 Death Clock segment filled.Your soul has been tethered to the afterlife. You can feel it pulling you back.
16-19If you are good, a celestial is hunting you, if you are evil, a fiend is hunting you. If you are neutral, a celestial or fiend (chosen at random) is hunting you. In any case, it is seeking to reclaim the lost soul. It always know your location, and it may be outright hostile or willing to parley.
20-24You always have the Frightened condition against the creature type that killed you. If you died to an environmental hazard, than that hazard has the same effect.
25-28Your age increases by 2d12. If this would exceed your ancestries average lifespan, roll a d20. On an 11 or higher, you return alive and the GM rolls 2d4. The result is your remaining lifespan. On a 10 or lower, your body withers and rots. You are dead.You have returned, but not with all of your vitality.
29-33You can no longer see colorYour eyes had become accustomed to the aesthetic of the realm of the dead, and aren’t adjusting to back.
34-50You gain a random quirk from a Resurrection Quirks quirk table.See Resurrection Quriks
51-55No effect.Nothing appears to be amiss.
56-60A deity, celestial, or fiend (GM’s choice) gives you a task to complete.You’ve been allowed to be brought back, but not without reason.
61-63You lose a level in your class and gain a level in Warlock. You can gain levels in either your existing class or Warlock.In exchange for your return, a patron demands your service.
63-65You lose a level in your class and gain a level in Cleric. You can gain levels in either your existing class or Cleric.In exchange for your return, a deity calls for your worship.
66-67Your alignment is randomly redetermined (you can end up with the same alignment).Something in the afterlife or the act of resurrection has changed or reaffirmed your outlook.
68-70You learn one piece of obscure, ancient, and/or lost knowledge.Sometime during your stay in the realm of the dead, you came across a piece of unique, esoteric lore.
71-76You gain darkvision out to range 60 ft. If you already have darkvision, its range increases by 30 ft.Your sight given to you in the realm of the dead has returned with you.
77-80you can make Recall Knowledge checks to recall a corpse’s or undead’s previous life.You walked the path of death alongside them. No matter their physical state, you recognize them.
81-85You gain immunity to the frightened condition.You have known death before. Nothing can be more terrifying than that.
86-90Increase your maximum Death Clock by 2.
99increase a mental stat of your choice (Wisdom, Charisma or Intelligence) by 1.
100Increase a physical stat of your choice (Dexterity, Strength or Constitution) by 1.

Resurrection Quirks

Credit: Original Table Here by Jack_of_all_Tricks on reddit. Slight modifications by me.