There's no point attacking a mob if a lower level mob is enough to give you max xp (3000 gross). What matters is xp/time rate.
Easy way: Just attack mobs who's level you could see, that's how it's meant I believe.
Better way: For max xp attack a mob who's level is: <highest skill level used in team> + 20 + (8 * <number of team members (excluding you)>).
Best/slow way: Have a try with different mobs and calculate the average xp/time rate, pick the mob that gives you best rate at your current level.
You could check any mobs level from http://ballisticmystix.net/?p=mob
Easy way: Just attack mobs who's level you could see, that's how it's meant I believe.
Better way: For max xp attack a mob who's level is: <highest skill level used in team> + 20 + (8 * <number of team members (excluding you)>).
Best/slow way: Have a try with different mobs and calculate the average xp/time rate, pick the mob that gives you best rate at your current level.
You could check any mobs level from http://ballisticmystix.net/?p=mob
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I don't want to be the oneThe battles always choose
'Cause inside I realize
That I'm the one confused