The buffalo is the highest-paid symbol. If you manage to get 6 times on the reel, you can get 300 times the line bet - it will also appear on all the reels in the base game. What you want is 6 extra 100 free spins that will allow you to total up to 200 free spins. More free spins can also be won indefinitely, which helps.
I found Buffalo Blitz to be a highly varied game where bigger wins apparently appeared in free-to-play features - this game does require patience, albeit much like Raging Rhino (WMS).