You get an emblem with "Pay 2 life: Add one mana of any color" and "At the beginning of your upkeep, you draw a card and you lose 1 life." If an effect would cause you to gain life past your maximum life total, you won't gain any life above your maximum life total
If the cost was paid, an opponent draws a card
This red enchantments at least guaranteed to mess with combat math
To be more specific, right now acquiring a 5th copy of a rare or mythic card feels absolutely awful
Understanding the phasing allow you to implement clever tricks
For example, if you somehow used Souls of the Lost to craft Mastercraft Raptor (perhaps because it became a copy of a Dinosaur), its power while in exile is equal to the number of permanent cards in your graveyard, and Mastercraft Raptor's power will change as the number of permanent cards in your graveyard changes