Feats or Class Featurs to manipulate results of HD rolls?

[Segev]

Start by assuming the base rules of 3.5/PF: Max HP at first level and rolled hp for every level thereafter.

I would like to discuss the merit or worth of either a feat or a class feature which allowed you to set a minimum acceptable result on a rolled hit die. A feat is obviously more general, but is also obviously in competition with Improved Toughness (+1 hp/level, period).

There are a few details to explore and examine:

• Does it set a below-par roll at the minimum par, or does it just let you re-roll until you get something above-par?
• The effect of an increase in the allowed minimum roll is greater the smaller the HD. For instance, a d4 that can't roll below a 2 has its average improve by .25, while a d10 that can't roll below a 2 only improves by .1, while a d4 that can't roll below a 4 is effectively always rolling max.
• For a class feature, setting a minimum for levels taken in that class has a more powerful incentive to not just dip it than would having it apply to all hit dice in any class.
• If a feat (or a class feature which applies to all HD), whether it's retro-active or not would make a difference in how potent it is.
• Is it's "interestingness" valuable enough to make it worth messing with over something that just gives flat bonus hp/HD?

[Yakk]

One of them is similar to how Brutal works in 4e. In general, Brutal X (reroll all dice that land on X or under until you get better) adds +X/2 to the average so long as X < max roll on the die.

The "if you roll X or under, you get replaced with X+1" sucks because it is useless with high HD, as you have noted -- (1/HD * (X^2)(X+1)/2).

A better way is "if you roll X or under, you get placed with max(HD)". (Call this Boosted(X)). At HD=d4 and X=1, this adds .75 per HD. At HD=1d12 and X=1, this adds 11/12 of a HD per HD. It has diminishing returns on increased X:
[MaxHD*X - X(X+1)/2]/MaxHD
but increasing returns with MaxHD. The rate of decrease goes up the lower the MaxHD is.

d4 Boosted 3 is always 4, or +1.5 over a raw d4.
1d12 Boosted 3 is 25% 12, 75% 3+d9 = (5+3)*.75 + .25*12 = 9 average, or +2.5 over a raw d12.

A good "intro" feat, or a side effect to add to this feat, would be a rules element that lets you reroll *all* of your old HD when you gain a level (taking sum if it is better than the old sum), then adding a new roll for your new HD. This reduces the penalty of getting these kind of feats late (but does not completely eliminate it).

[Segev]

Hm. Interesting thoughts.

I don't know if this is just me, or if most people keep track of each individual HD roll. (I do so so that, if I lose levels, I lose the right number of hp, rather than having to roll or take average or something.) If the intro feat allowed you to re-roll every HD at every level, and take the roll if it's higher than what you got last level for that HD, that would be potentially very potent.

[Just to Browse]

I frown upon mechanics that require you to do level-based calculations retroactively (I'm looking at you, Constitution), but I also frown on mechanics that are less effective if you pick them up later in your career. So I'm not a big fan of things that change your hit die unless they're "level 1 only" feats.

[TheFamilarRaven]

In a group I play with they homebrew in a rule that you can't roll below your CON modifier when rolling HD. If the roll lands on a number below your CON mod, reroll. Otherwise, that's your hit points, and the effects aren't retroactive. Dunno if you wanna make that a feat or not, but it's a suggestion.

[Segev]

It's an interesting suggestion.

Of note, I have found the things that are NOT retro-active to be more irritating, because it makes building characters (NPCs as well as PCs) harder at higher level. Skills, for instance, have to be tracked all the way up, rather than simply calculating a skill point total based on your levels and current int mod and classes.

[Ilorin Lorati]

In a group I play with they homebrew in a rule that you can't roll below your CON modifier when rolling HD. If the roll lands on a number below your CON mod, reroll. Otherwise, that's your hit points, and the effects aren't retroactive. Dunno if you wanna make that a feat or not, but it's a suggestion.

Interesting rule; what were the considerations for a character with a small HD and a higher con mod than their HD size? Just take max?

[TheFamilarRaven]

Interesting rule; what were the considerations for a character with a small HD and a higher con mod than their HD size? Just take max?

pretty much. it's a pretty relaxed group, and rules are very much in favor of PC's, although the rules still apply for NPC's as well.

Example, stats are a standard array of 20,18,16,14,12,10. I made a wizard with a INT of 20 and a CON of 18 ... So yeah .. I get max HP (most of the time ... it IS PF). This rule is not for everyone, but i felt like it fit the theme of the question.

[Segev]

It certainly is in line with the kind of thing I was hoping to see in this thread, so thanks for sharing. ^_^