Making an event hapen once...

How do i make it so an event only happens once FOREVER. I know the 'Erase Event' erases it for that session(if you shutdown the game, it plays again, and if you leave then come back, it plays again).

How do I make it happen only once? I have it on Parrel process so it starts when you enter this room, but I want it to happen once and once only.

Simple enough. At the end of the event, turn on a self switch. Then, click new event page and set the conditions so that it only starts when that self switch is on.

This belongs in troubleshooting. Strike 1.

How exactly do I do this?

Is their a event command in the list that turns on the self switch, or do I just make the self switch A 'On' by clicking the box next to it?

It's an event command.

Control Self Switches >>  Self Switch A on.  Fist event page, second column, 3rd command.

I made a self switch and I make the process a conditonal branch.

If self switch  == on

The event no longer plays when I enter the room.

You don't need a conditional branch. Make your event as you did before, and at the end of the event, use the command "Control Self Switch" and set Self Switch A to on. Next, click "New Event Page" (which is located right next to the name of the event at the top of the page), and in the box that says Conditions, click the checkbox for Self Switch.

Do you understand?

But after the event is done don't I need to set it to turn the switch OFF so it doesn't play again?

EDIT: The event won't play at all still after doing what you suggested...

No.  After the event plays though, then you turn the self switch on, do as Zylos said with the new page, and leave the second page completely blank.

Look at it this way. You are making one event with two pages. The first page is what you want your event to do, and the second page is blank. At the end of the first page, you turn on the self switch. This switch tells your event to read the second page instead of the first page for as long as that switch is on. But because the second page is blank, nothing will happen. So as long as that self switch is on, your event will read the second page and do nothing, just like you want it to do.

Well as it stands now the event doesn't even play when I enter the room.

Make sure that page one has nothing checked in the conditions box, and that you turned the self switch on at the end of the event instead of at the beginning. Also make sure that you do have the Self Switch checked in the conditions of the second page. It should be working.

Thanks for your help!

I just have one more bug I need to fix.

I have it so when you talk to the main NPC of the story he asks
'Did my father send you to get me'?
YES
or
NO

If you say no nothing happens he just says 'Alright. Good.'

If you say yes he starts to move away from you(on a SET MOVE ROUTE) and there is text going on at the same time(after the SET MOVE ROUTE I have text commands) and if you skip through all the text he can just disappear before he is off screen(because of ERASE EVENT command being after the text.)

How can I make it so the text doesn't end until he is off screen?

Wait For Move's Completion.

Right under Set Move Route.

EDIT:  Wait, you want the text while he's moving?  I think you need a Message Script.  I use Ccoa's UMS.