|1||-2||This champion gets +2 DMG and Careless|
|2||7||This champion gets +1 SPD, +3 DMG, and Careless|
|3||14||This champion gets +2 SPD, +4 DMG, and Careless|
Berserker champions get their boosts as a set, and thus usually are cheaper as a result of not being able to save AP. Thus, they are great for melee champions to engage your opponent and start doing significant damage.
Since Berserker champions don't save AP, 6 speed Beserker champions almost always upgrade to Berserker 3 so they get 8 AP at the start of their turn (enough for 2 attacks), Champions with only 7 AP are at a significant disadvantage unless they can get 2 attacks some other way or have some other role.