Dreams of the Dead — ruling 1

If a permanent has multiple instances of cumulative upkeep, each triggers separately. However, the age counters are not connected to any particular ability; each cumulative upkeep ability will count the total number of age counters on the permanent at the time that ability resolves.

Dreams of the Dead — ruling 2

If a creature returned to the battlefield with Dreams of the Dead would leave the battlefield for any reason, it’s exiled instead — unless the spell or ability that’s causing the creature to leave the battlefield is actually trying to exile it! In that case, it succeeds at exiling it. If it later returns the creature card to the battlefield (as Oblivion Ring or Flickerwisp might, for example), the creature card will return to the battlefield as a new object with no relation to its previous existence.

Dreams of the Dead : règles, fonctionnement et interactions (MTG)

Dreams of the Dead is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

: Return target white or black creature card from your graveyard to the battlefield. That creature gains "Cumulative upkeep ." If the creature would leave the battlefield, exile it instead of putting it anywhere else. (At the beginning of its controller's upkeep, that player puts an age counter on it, then sacrifices it unless they pay its upkeep cost for each age counter on it.)

How it works : Dreams of the Dead

Original English text — Wizards of the Coast / Scryfall

#1April 15, 2013· Wizards of the Coast
If a permanent has multiple instances of cumulative upkeep, each triggers separately. However, the age counters are not connected to any particular ability; each cumulative upkeep ability will count the total number of age counters on the permanent at the time that ability resolves.
No other card is named in this ruling.
#2October 1, 2008· Wizards of the Coast
If a creature returned to the battlefield with Dreams of the Dead would leave the battlefield for any reason, it’s exiled instead — unless the spell or ability that’s causing the creature to leave the battlefield is actually trying to exile it! In that case, it succeeds at exiling it. If it later returns the creature card to the battlefield (as Oblivion Ring or Flickerwisp might, for example), the creature card will return to the battlefield as a new object with no relation to its previous existence.
No other card is named in this ruling.
#3October 4, 2004· Wizards of the Coast
This is a replacement effect.
No other card is named in this ruling.