In battle there are proper heros.
In battle many people clash, few (except in situations where one team rolls the other), are left standing.
The tactics available, (ok not very imaginative ones) like camp the hill, camp the spawn, shieldwall and zerg rush, left and right.
Killing a player means he's dead until the next round, provides good reasons to get revenge which could evolve into a friendly rivalry.
And the most important thing about battle to many players. The scoreboard. Players who reach the top of the scoreboard often are players people get to know, sometimes this is a good thing, many times it's a bad thing (like being targeted specificly by enemies) but it provides people with new challenges. But the major bonus with topping scoreboards or getting to the top 10 means you get attention. Since most people crave attention this is a good thing.