Here's an example.
We have two bricks, right?
One is named "trigger" and one is named "rocketShooter"
For "trigger", I put these events:
onActivate>(Named Brick)rocketShooter>fireRelay
For "rocketShooter" I put these events:
onRelay>self>spawnProjectile 0 5 15 Gravity Rocket 0 0 0
This makes it so when you click "trigger", it'll fire a relay to rocketShooter which has an event that tells it to fire a rocket when it gets a relay.
"trigger" fires a relay to "rocketShooter" and "rocketShooter" then fires a rocket.