The X-Iter is the Buy Bonus feature in Toro Shogun. Once activated, it lets you purchase one of the different bonus options in the game, so you can go straight to them:
Bonus Hunt- costs 3x the current bet
Toro Spin - costs 10x the current bet
Shogun Spin- 25x the bet
Buy Bonus - 100x the bet
Shogun bonus - 500x the bet