I was thinking about the current guest framework and I had the following thought:
What if you were to implement a feature by which a cookie was created that only lasted until the browser was closed (session cookie see answer to this stack overflow question) so that the amount of bones and the arena rank of guests was saved until the browser was closed? It would allow for more guest 1v1 in allowing guests to have a temporary score. As an aside, you could add a guest scoreboard under the trophy menu on the start screen to list the highest ranking currently playing guests.
Also, because of the 1 post per week rule, here's another idea:
A time out for the charge attack. Simple as that. After something like 3-5 seconds, the charge attack "times out" (the attack just disappears, it doesn't discharge). This would solve the problem of people holding the attack for ever then letting go after people block. Or, alternatively, have the attack drain the stamina bar the longer it's held, then have it disappear (not discharge).
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