Since there seem to be some people who are interested in how I plan to convert knight. I've taken some of the opinions of it on these boards into consideration, and have made some additional tweaks for realism purposes (specifically the Shield Ally class feature).
To be fair, I have definitely added more power to the class than many of you have suggested is required, but I am rather skeptical that the abilities Knight is given stack up to some of the equivalent classes available in Pathfinder. That being said, I am willing to hear comments and criticisms regarding this conversion, and would be happy to discuss points of contention. My primary interest here is making a class that will be balanced and won't require too many tweaks, as this character will be played by a new-ish player to D&D/Pathfinder.
Here are the details:
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Fighting Challenge (Ex) 1st
The rate at which the bonus to Fighting Challenge improves has been altered such that at 5th level and every 4th level thereafter, the bonus increases by 1 (+2 at 5th, +3 at 9th, +4 at 13th, +5 at 17th).
Test of Mettle (Ex) 4th
In addition to its usual effects, Test of Mettle provides the knight a morale bonus to her AC equal to her Fighting Challenge bonus against the creatures affected by Test of Mettle only.
Shield Ally (Ex) 6th
As an immediate action, a Knight may respond to a melee attack against an adjacent willing ally by entering the ally's space. This results in both the Knight and her ally having 50% odds each of being targeted by the attacker. The attacker must roll a percentile die for each attack: 1-50 targets the knight's ally, 51-100 targets the knight. The knight may choose to take a -4 penalty to AC until her next turn to have 75% odds of the attacks against her ally to be treated as attacks against her instead. Once all attacks against the knight's ally have been resolved, the knight may choose an adjacent space to eject her ally to as a 5-foot step (for the ally). During the ally's next turn, his movement speed is reduced by 5 feet to account for this.
To perform this action, the knight must have at least 5 feet of unused movement left over from her previous turn.
Improved Shield Ally (Ex) 12th
This class feature operates as Shield Ally, but does not require that the knight have 5 feet of unused movement left over from her previous turn to be performed. Additionally, the knight may choose to take a -4 penalty to AC to ensure that all attacks against her ally are treated as attacks against her instead.
Greater Shield Ally (Ex) 18th
This class feature operates as Shield Ally, but when sharing an ally's space, the knight has 75% odds of being targeted by attacks against her ally. The attacker must roll a percentile die for each attack: 1-25 targets the knight's ally, 26-100 targets the knight. The knight may take a -2 penalty to AC until her next turn to ensure that all attacks against her ally target her instead. Additionally, the knight can perform this special attack of opportunity action to respond to an attack against an ally up to 10 feet away, as long as the knight has at least 10 feet of unused movement left over from her previous turn and there is line of effect between the knight and her ally.
Armor Mastery (Ex) 19th
At 19th level, a knight gains DR 5/— whenever she is wearing armor or using a shield.
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The change to Shield Ally is in response to its original definition allowing the knight to take half damage for the shielded ally. I honestly cannot visualize how one could take half of the damage from each blow. It just doesn't work in reality. So instead, I've converted this to probability, which makes a lot more sense here than a straight up division. It takes more rolling, but I think it'll be a lot more suspenseful, and it behaves more accurately with regards to DR.
Let me know what you think.
P.S. There are a few more posts here now than there were, so I'm looking into them and how they compare.