Bretonnian Knights often form up into a powerful formation called the 'Lance'. This formation enables the Knights to charge deep into enemy units, angled so as to maximise the number of attacking Knights.
Source: Warhammer Armies Project: Unofficial 9th Edition (v2.2)
Lance FormationURL Copied!
Any Cavalry unit with this special rule may deploy in the Lance Formation and/or reform into it during the game. A unit in Lance Formation follow the rules for Ranks that apply to Monstrous Cavalry. In effect, if by any means a unit of Bretonnian Knights is formed into a unit three models wide, it is treated as being in Lance Formation. Note that if a unit is ever wider than three models, it no longer counts as being in Lance Formation. In addition to this, the unit may form a unit up to 5 ranks deep.
A Wizard may be placed in the centre of the second rank of the Lance Formation rather than the front rank, as the Knights form up protectively around her. Note that she remains fully in play even if she is not in the front rank (so the unit may use her Leadership, she may cast magic, etc.). If a second Wizard joins the unit, she may be placed in the centre of the third rank. If the rank in front of the Wizard ever falls below three models, she will move forward to take up the empty space. A Wizard in the second rank still counts as having line of sight for the purpose of casting spells.
On a turn that a unit in Lance Formation makes a successful charge, all models with this special rule gain the Fight in Extra Ranks (1) special rule, and every rider that gets to fight can make up to 3 Supporting Attacks rather than 1. In addition, they add their current Rank Bonus to the Strength of the Impact Hits they inflict. Finally, if the unit wins that round of combat, it also counts as having double their actual Unit Strength for the purpose of determining if the enemy unit is Steadfast or not.