What are some examples of cards in Magic the Gather that use the rule 115.2c?
115.2c Some effects allow a player to take an action at a later time, usually to end a continuous effect or to stop a delayed triggered ability from triggering. Doing so is a special action. A player can take such an action any time they have priority, unless that effect specifies another timing restriction, for as long as the effect allows it.
An example of this (very rare) special action would be paying {U} to prevent the delayed trigger from Quenchable Fire.
Quenchable Fire {3}{R}
Sorcery
Quenchable Fire deals 3 damage to target player or planeswalker. It deals an additional 3 damage to that player or planeswalker at the beginning of your next upkeep step unless that player or that planeswalker’s controller pays {U} before that step.
There are three other cards with a similar template that also use 115.2c: Glass Asp, Nafs Asp, and Sabertooth Cobra.
The Licids from Tempest block also use 115.2c to enable you to end a continuous effect:
Calming Licid {2}{W}
Creature — Licid
{W}, {T}: Calming Licid loses this ability and becomes an Aura enchantment with enchant creature. Attach it to target creature. You may pay {W} to end this effect.
Enchanted creature can’t attack.
