|The other Collider2D involved in this collision.
Sent each frame where another object is within a trigger collider attached to this object (2D physics only).
Further information about the other collider is reported in the Collider2D parameter passed during the call.
Note: Trigger events will be sent to disabled MonoBehaviours, to allow enabling Behaviours in response to collisions.
See Also: Collider2D class, OnTriggerEnter2D, OnTriggerExit2D.