The bot analyzes the last ticks and buys the "over 2" contract using the following criterion: the last 4 ticks are in a decreasing sequence (e.g., 9-5-4-1), then it triggers the purchase. A Martingale of 2.5 is applied to recover losses.
This idea has an approved bot implementation that is ready for download. Note that this bot only works on the D-Apollo platform.