Okay, saw what people says about 14 - I have a better strategy:
1. Stomp on near bat
2. Before hitting the spikes, stomp to avoid the ghost, eat the higher bat to reach the right side safely
3. From there stomp on the lower bat, stomp on the higher bat, eat the skull
4. Jump down and eat the bat to reach the upper left side
I think this is the intended one as the harder one leaves a bat unused.
Hope this helps :)
I am working on this atm :)