Special Actors: Spawn and Check
Sometimes you want to create a group of actors that are associated for a common purpose, for example, you want to create a power-up item but only by destroying a group of enemies, actors are for this.

actors do not have spritesets because they are invisible to the player, they have the following properties:
: spawn layer, and float state.
: score for a completed (destroyed) spawn.
: swap to other actor when completed (destroyed), for example, a power-up item.

are created on the behaviour panel, only actors are taken into acount for the group, use the spawn icons to crete them, each step must have at least a and a icon, once the last step is reached the spawn point will turn from green to red so its completed and will wait until all created enemies are killed.
Sometimes you necessarily need to check the game state, for example, you need to know when the stage has ended because you defeated a boss, or open a door if all keys have been picked up, actors are for this.

: checking condition, checks if an actor does not exits or if exists a minimum amount of them, for example, fighting 3 final bosses, swap them to other actor when killed (a plain actor), you just need to check if there are 3 of those actors to confirm that the stage is over.

: triggers the end of the stage event. ( properties of the stage)
: all enemy actors are hitted by the indicated amount.
: Swaps defined actors to another ones, if no destination is set, actors are deleted. You can use this to change your hero to another more powerful, open doors (deleting the door).
: increments player score.

Once done actor it removes itself.