Idea: Collect all letters in the English alphabet from the names of the MTR stations you visit. Rule 1: You may only collect 1 letter per station. Visiting the same station twice does not allow collection of 2 different letters. Rule 2: You must collect the letters in alphabetical order. For example, you may not collect the Q from Quarry Bay until after you collect the letter P. Rule 3: You may not leave the paid area unless it is for interchanging at Tsim Sha Tsui, ETST, Austin or Kowloon station. Rule 4: You must start at Mong Kok East. Rule 5: Everytime you change trains (for interchanging or for reversing direction), Rule 4 is changed into a new rule.