Firstly there is no official rule list for SkyWars (non-evolved, but evolved might not have official rules either) But the main reason I am bringing this up is because i recently encountered a game (i cant quite remember the username but it started with 'I_') that lasted a minimum of 25 minutes, everyone but me and him were dead by the five minute mark, yup, you guessed it, he ran FOR 20 MINUTES! As you can imagine i had GREAT fun chasing him for this length of time and felt like if it ever happened again i would smash my monitor, i would like to see a game length limit where as either: both player get trapped in the middle area to fight (however small it is), or get teleported to a new small arena that has little space to run away and you are unable to place blocks within, or finally, just make a general rule against it (this would mean the creating of an in-game timer and i understand that might be a lot of work). Im sure some have experienced a game similar to mine (though probably not as extreme) and would agree with this ruling.