Coveted Prize — ruling 1

If you have a full party and wish to cast a spell with Coveted Prize's effect, you do so as part of the resolution of Coveted Prize after searching for a card. You can't wait to cast it later in the turn. Timing permissions based on a card's type are ignored.

Coveted Prize — ruling 2

The card you search for may be the one you cast.

Coveted Prize — ruling 3

If you cast a card "without paying its mana cost," you can't choose to cast it for any alternative costs. You can, however, pay additional costs. If the card has any mandatory additional costs, you must pay those to cast the card.

Coveted Prize — ruling 4

If the card has {X} in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.

Coveted Prize — ruling 5

To determine "the number of creatures in your party," check whether you control a Cleric, whether you control a Rogue, whether you control a Warrior, and whether you control a Wizard. The number is the total number of those checks to which you answered yes. Each creature you control can be counted for only one of those checks.

Coveted Prize — ruling 6

If a creature has more than one party creature type, and there are multiple ways to count that creature that could result in a different number of creatures in your party, the highest such number is used. For example, if you control a Cleric and a Cleric Wizard, the number of creatures in your party is two. You can't choose to have it be just one by counting the Cleric Wizard first as a Cleric.

Coveted Prize — ruling 7

An ability referring to the number of creatures in your party gets a number from zero to four. Such abilities never ask which creatures are in your party, and you never have to designate specific creatures as being in your party. You can't choose to exclude creatures from this count to lower the number.

Coveted Prize — ruling 8

Some cards refer to you having a "full party." This is true if the number of creatures in your party is four.

Coveted Prize : règles, fonctionnement et interactions (MTG)

Coveted Prize 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

This spell costs less to cast for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.) Search your library for a card, put it into your hand, then shuffle. If you have a full party, you may cast a spell with mana value 4 or less from your hand without paying its mana cost.

How it works : Coveted Prize

Original English text — Wizards of the Coast / Scryfall

#1September 25, 2020· Wizards of the Coast
If you have a full party and wish to cast a spell with Coveted Prize's effect, you do so as part of the resolution of Coveted Prize after searching for a card. You can't wait to cast it later in the turn. Timing permissions based on a card's type are ignored.
No other card is named in this ruling.
#2September 25, 2020· Wizards of the Coast
The card you search for may be the one you cast.
No other card is named in this ruling.
#3September 25, 2020· Wizards of the Coast
If you cast a card "without paying its mana cost," you can't choose to cast it for any alternative costs. You can, however, pay additional costs. If the card has any mandatory additional costs, you must pay those to cast the card.
No other card is named in this ruling.
#4September 25, 2020· Wizards of the Coast
If the card has in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
No other card is named in this ruling.
#5September 25, 2020· Wizards of the Coast
To determine "the number of creatures in your party," check whether you control a Cleric, whether you control a Rogue, whether you control a Warrior, and whether you control a Wizard. The number is the total number of those checks to which you answered yes. Each creature you control can be counted for only one of those checks.
No other card is named in this ruling.
#6September 25, 2020· Wizards of the Coast
If a creature has more than one party creature type, and there are multiple ways to count that creature that could result in a different number of creatures in your party, the highest such number is used. For example, if you control a Cleric and a Cleric Wizard, the number of creatures in your party is two. You can't choose to have it be just one by counting the Cleric Wizard first as a Cleric.
No other card is named in this ruling.
#7September 25, 2020· Wizards of the Coast
An ability referring to the number of creatures in your party gets a number from zero to four. Such abilities never ask which creatures are in your party, and you never have to designate specific creatures as being in your party. You can't choose to exclude creatures from this count to lower the number.
No other card is named in this ruling.
#8September 25, 2020· Wizards of the Coast
Some cards refer to you having a "full party." This is true if the number of creatures in your party is four.
No other card is named in this ruling.
#9September 25, 2020· Wizards of the Coast
Several cards have a cost reduction based on the number of creatures in your party. To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions. The mana value of the spell is determined only by its mana cost, no matter what the total cost to cast the spell was.
No other card is named in this ruling.
#10September 25, 2020· Wizards of the Coast
If a spell has a cost reduction based on the number of creatures in your party, no player may attempt to change that number after you begin to cast the spell but before you pay the cost.
No other card is named in this ruling.