As Phenomenon Investigators enters, choose Believe or Doubt.
• Believe — Whenever a nontoken creature you control dies, create a 2/2 black Horror enchantment creature token.
• Doubt — At the beginning of your end step, you may return a nonland permanent you own to your hand. If you do, draw a card.
If you somehow control Phenomenon Investigators and no choice was made for it (perhaps because another permanent on the battlefield became a copy of it, or it was manifested and later turned face up), it has neither of the two triggered abilities, no matter how much you want to believe (or doubt).
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.