Take 10 is a great way to allow a character to do a decent amount of stuff without having to invest a terrible amount of skill points. For instance, a +5 climb with take 10 will let you climb a lot of surfaces when your not distracted.
The problem comes when combat ensues, all of a sudden you have a 45% chance of not making the check. Okay, that's not so bad, afterall you only have a +5.
However, even with a +10 in climb, meaning you are exceptionally trained or are so strong you can break solid rock with your bare hands...you still have a 20% chance of not making the simple DC 15.
So here's my rule, if you take a -5 to a skill check, you can take 10 on that check as if you were in a nonstressful situation, unless you cannot ever take 10 with that skill. You must have at least 5 ranks in the skill to do this.
So in this example, the person with the +10 climb check can make DC 20 climb checks easily when not distracted, and can make DC 15 checks easily even in the heat of battle.
Basically, this helps bridge the power gap in skill ranks needed. Normally a person would need a +14 in climb to be able to make DC 15 all the time. That's requires a lot of climb ranks. Now you can do it with a +10, which is a little more managable.
The net effect is that it allows characters to be consistently good at skills in combat with a good amount of training, but not the overwhelming amount required by the rules as is.
Also note that you cannot take 10 on skills like diplomacy and bluff because you cannot ever take 10 with them.
Edit: Made it so you have to have 5 ranks in the skill to use this mechanic, so that at least some formal training is there.
The problem comes when combat ensues, all of a sudden you have a 45% chance of not making the check. Okay, that's not so bad, afterall you only have a +5.
However, even with a +10 in climb, meaning you are exceptionally trained or are so strong you can break solid rock with your bare hands...you still have a 20% chance of not making the simple DC 15.
So here's my rule, if you take a -5 to a skill check, you can take 10 on that check as if you were in a nonstressful situation, unless you cannot ever take 10 with that skill. You must have at least 5 ranks in the skill to do this.
So in this example, the person with the +10 climb check can make DC 20 climb checks easily when not distracted, and can make DC 15 checks easily even in the heat of battle.
Basically, this helps bridge the power gap in skill ranks needed. Normally a person would need a +14 in climb to be able to make DC 15 all the time. That's requires a lot of climb ranks. Now you can do it with a +10, which is a little more managable.
The net effect is that it allows characters to be consistently good at skills in combat with a good amount of training, but not the overwhelming amount required by the rules as is.
Also note that you cannot take 10 on skills like diplomacy and bluff because you cannot ever take 10 with them.
Edit: Made it so you have to have 5 ranks in the skill to use this mechanic, so that at least some formal training is there.
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