Actually, I have spent more than $20 but looks like it was my unlucky day. Sometimes, the inside feeling leads me to bet more or increase the bet and it worths keeping spinning until the bonus round. If it is an unlucky day for me and already $20 is wasted I will come back another day. Tomb of Nefertiti was good but the winnings are limited to 3 re-spin in 10 free spin mood and wilds are not stuck, unlike other profitable slots.