Timers
Timers are essential blocks for timing certain events. Certain portions of gameplay can be restricted by a timer. Super Mario Bros has a level timer by which the player has to finish the level, otherwise he dies. Super Smash Bros has a match timer which limits the duration of a match during which players have to defeat one another.
Timers play an essential role in many aspects of game play. Spawner has a timer which tells when a certain object or enemy spawns. Spells have very often cooldowns a timer which tells for how long does the player have to wait until they can activate the spell again.
Bomberman bomb explosion

Duration
Timers have duration in seconds at which the timer has to trigger an event.
Cycles
Timers can repeat them selves or they can be a one time event. They can be specified by the number of cycles.
Events
The event which has to be triggered when the timer ends.
Implementation
- Duration in seconds
- Coroutine which waits for duration before it executes event.
- Event, trigger an even when the timer ends.