Get Fireheart to spottedleaf, when you touch spottedleaf (calico cat) you go to the next level, at the third level (there are four) tigerclaw will go about randomly, you can only touch him before you move, after you respawn or at the beginning of the level. w a s d or arrow keys to move.
Warriors by Erin Hunter. I did this for school. When you win all the levels and are on the last slide (the You Won!!!!!!!!!!!!! slide) at the top right corner is Sandstorm, I won't say why bc its kinda spoiler so only people who have read the whole first series (at least) will get it.
