Trying it without the feat (3.5e Variant Rule)
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 Trying it without the feat
DnD allows for many heroic maneuvers and cool stunts. It's just too bad that to do most of them, you need the right feat. With this variant rule, PCs are allowed to try anything they could do with the right feats if they are willing to take a little risk. This house rule is best combined with action point and a heroic setting like Eberron.
 The house rule
If a PC attempts something that requires a feat he does not have, he can do it, but with a -4 penalty to any required D20 roll. For any prerequisite of the feat he does not fulfill, he takes an additional -2 penalty to the roll(s).
- Feinting as a move action (Feat: Improved Feint, prereq Int 13, Combat Expertise). You take a -4 penalty to your Bluff check.
- Tracking footprints (Feat: Track), you take a -4 penalty to your Survival check.
- Taking a second Attack of Opportunity in a round (Feat: Combat Reflexes) You take a -4 penalty to your attack. As with the feat, you can't attempt more AoOs in a round than you have Dex bonus.
- Punch someone without provoking an AoO: you take a -4 penalty to your attack
- Feats that do not involve some kind of check cannot be attempted. For example, you can't try to Run 5 times your move in a round, as per Run feat, because no d20 roll is involved.
- If the feat is limited in some way, you are still bound by that limit. For example, you can't make more Attacks of Opportunity in one round than you have Dex bonus.
- You do not gain any numeric bonuses a feat grants. For example, you can attempt to Trip someone without drawing an AoO and you can get an attack against someone you tripped, as per Improved Trip, but you don't get a +4 bonus to Trip attempts if you don't have the feat.
 Bonus rules
- Attempting Item Creation: You can attempt to create an item, even if you don't have the relevant item creation feat (you must still be able to cast the relevant spells). Creating an item this way costs 75% of the market price in gp, 1/20 in XP and you can only create 500gp worth of the item in one day.
- Attempting metamagic: You can attempt to boost your spells without the right metamagic feat, but doing so boosts the spell by another spell level and you must succeed at a Spellcraft check DC 10 + 2x spell level.