For the purposes of MS (kill hundred thousands of monsters per level) I'd define Kill Stealing as any action which affects the training rate of someone else in the same map as you.
Doesn't matter if they hit the targets first, if they are heading toward monsters and you kill them it's KSing, unless they respawn in time. If you are splitting a map, the first person there decides how it is split. You can't just waltz in, wait for them to be on another platform, and start attacking in the best area, if they want that part of the map, give it to them.
On "FFA" bosses where anyone can get in, politeness demands that the first person to arrive who is prepared to kill the boss gets priority, and if they don't invite you to help, gtfo. (note that being afk in the map does not count as prepared) With the way boss spawns work in MS, there is nothing more obnoxious than some 4th job pimento who abuses their power to kill the boss you might only find first once a week.
Doesn't matter if they hit the targets first, if they are heading toward monsters and you kill them it's KSing, unless they respawn in time. If you are splitting a map, the first person there decides how it is split. You can't just waltz in, wait for them to be on another platform, and start attacking in the best area, if they want that part of the map, give it to them.
On "FFA" bosses where anyone can get in, politeness demands that the first person to arrive who is prepared to kill the boss gets priority, and if they don't invite you to help, gtfo. (note that being afk in the map does not count as prepared) With the way boss spawns work in MS, there is nothing more obnoxious than some 4th job pimento who abuses their power to kill the boss you might only find first once a week.