support vision: Android API 27 by Hardys
After splash animation, there will be three buttons. The top one let you start the game, the second one let you select the difficulity of the game, the bottom one has a list of reference for those pictures.
There are 5 * 10 boxes and total 10 zombies (by default). Once user click a box, it could either show it is a hit or a miss. If it is a hit, a zombie will be shown and num of zombie left decrements; if it is a miss, it shows a number to tell user how many zombies left at the row and column corresonding to the box user clicked. Once user finds all zombies, user wins.