Can I purchase tickets when i get to the illusion museum or do i HAVE to order online?

Yes you can. They are pricee the same

Same price for purchasing online or on site.

You can buy tickets at the our front desk. However, tickets purchased online guarantee you entrance on busy days such as weekends and holidays

You could do either...

Same price if you purchase online or on site

If you go thru Gold star, it's$5 cheaper.