A second, much more skill based strategy for challenge 4 is to order shield to follow sword, and then strafe REALLY hard. You need to keep shield between you and dragon, just imagine yourself as sword. Bring shield forward by going along a side and then moving behind him quickly, allowing dragon to target shield. Avoid getting close to the dragon, or having shield in the way of your line of sight, otherwise your shots will miss.
I figured out how to do challenge 4.
Dragon will target the bot closest to him, HOWEVER, his gun cannot shoot directly near him. Therefore he will automatically aim at sword, because sword is using the same game with the same range. You have to micro manage shield constantly in order to prevent him from coming too close to dragon, and from getting farther away than sword, while having sword on "follow" on dragon. This strategy also takes a lot of luck, but you can eventually get it.
This game. Absolutely beautiful bit of work. Gonna have to rate it up there with the crazy philosophical bullshit I read on a day to day basis.
Good job, with any luck you'll be the next Pratchett.
 "Bot Arena 3"){kind=icon}
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