Each unit starts with D6-1 experience. Note that this experience system does not cover Characters or War Machines. Characters should simply use the 'Veteran Characters' rules detailed in the WHFB Battle Book.
Units can be one of five levels, depending on the number of experience points they have.
XP's Level 0 Inexperienced Youth 1-5 Fresh Blood 6-10 Veteran Warriors 11-20 Elite Warriors 21+ Feared and Respected Reginment
The level of the unit has the following effect. Note that a unit keeps the bonus of the previous level when it advances to higher level. Obviously, when a unit drops from a higher to a lower level, it loses the bonuses gained from that higher level.
D6 Effect 1 May increase all their close combat results by 1. 2 Can automatically passes one leadership test they are called on to make. 3 Musician costs the same as a normal warrior (not double). 4 Standard Bearer costs the same as a normal warrior (not double). 5 The unit is toughened by its various encounters. It's saving throw may never be modified below 6+. 6 Unit causes Fear
+1 For taking part in a battle.
+1 If the unit was on the winning side in a battle.
+1 For breaking or wiping out a unit in hand to hand combat.
+1 For shooting at a unit and causing it to fail a panic test.
-2 If the unit was destroyed or fleeing at the end of a battle.
-1 For every new recruit added to the unit. Note that giving an existing meber a standard does not incur any penalty. Recruiting a champion force a unit to lose an XP, but placing any other type of character does not.