Maintenance cost

A Maintenance Cost is a (mostly optional) cost required to keep a card on the field. Both Monster, Spell, and Trap Cards can possess a Maintenance cost. These costs are typically paid during a player's Standby Phase, although there are exceptions to this.

Here are come cards with Maintenance Costs:

Monster Cards

 * Archfiend Cards

Spell Cards

 * Messenger of Peace

Trap Cards

 * Imperial Order
 * Mirror Wall

In the case of Archfiend Monster Cards, there is no option to destroy the monster card if you don't want to pay the cost, since the cost really is compulsory.