The trick to getting a high score is to get a massive chain. I got chain 16 and ended up with a total score of 80000 at the end. Great Time waster game =)
Personally to the arena problem I think with the arena problem that the easiest solution to avoid runners is not to make the one with the most units win (people could just start running from the start) but to make the person who deals the most damage win. That would be the best i think. + if you agree
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