One of my complaints about 4e and Skill Challenges was the lack of involvement in the out-of-combat system in character options. This was a deliberate design decision because they did not want to force players to choose between combat effectiveness and non-combat effectiveness, so they divorced rituals from attack powers. However, this means every single character choice upon levelling-up is related to combat and no option after character creation affects Skill Challenges. Unless you're blowing a feat to train in additional skill or are taking the one power that mentions Skill Challenges.
Likewise, the resource management aspects of the game just stop once Skill Challenges begin; much of what makes 4e the game it is just ends. Being less codified and not technically divided into rounds, there's few hard rules limiting the use of At-will powers or even Encounter powers during Challenges. Unless the Skill Challenge is explicitly timed, there's nothing preventing a PC from "disengaging", taking a 5-minute breather, and then using the same Encounter power to auto-succeed a second or third check. At the same time, there's nothing to encourage the use of other resources in Skill Challenges.
Skill Challenges are theoretically the safest method of earning experience as there's no penalty for success, no hard penalty for failure, and no limit on the number of Skill Challenges you can engage in during a single day. They're unlike and divorced from combat and 80% of the rules and resources of the game, seeming like a forgettable and tacked-on subsystem.
This blog is on some House Rules and variant rules for Skill Challenges.
Earlier this week, I posted a blog on playing in Skill Challenges and mentioned the option to just "say what you do" rather than using a specific skill. The other problem is that sometimes an action just does not fit a skill. The three physical skills (Athletics, Acrobatics, and Endurance) equate well with raw bodily prowess but there's no mental equivalent, a "common sense" or "smarty pants" skill for Wisdom or Intelligence respectively.
In cases where a skill just doesn't fit it becomes more of a straight ability check, which is the equivalent of an untrained skill. There's little reason straight ability checks can't be usable in Skill Challenges. Even for the physicals skills sometimes specialized training just won't help. Training in Athletics won't help much if you're trying to lift a heavy object, it's just a matter of straight physical strength.
The most common ability check for Skill Challenges will be Intelligence for memory and recall. Sometimes a random bit of trivia is needed or fits the Skill Challenge.
There's no reason to use Action Points in a base Skill Challenge. As characters can choose to act or not to act there's little incentive to act twice, even if your character is the only one with appropriate skills (which is actively discouraged). Unless the DM is counting rounds towards failure, speed is just not an issue.
Instead, Action Points could be used to cancel failures or re-roll checks. I've seen this done in-combat as a house rule and have allowed it myself: it doesn't really increase the chance of hitting, but means instead of missing on your daily just to spent the AP and use an at-will (with warlord bonuses) you have a chance of not wasting your daily. If the character is willing to sacrifice a free attack in a later combat for a chance at success in a Skill Challenge that is a fair trade.
This house rule does affect play and design. Skill Challenges that are the only encounter of the day or that take place over the course of several days might have to be exempt. The intent is that spending a limited resource confers a benefit, but if it is a resource that will be restored after without penalty then there was no cost. A DM implementing this house rule should try to have Skill Challenges followed or preceded by combat, so that every player has a free failure cancelation. The ability to reduce failures does give a DM freedom to increase DCs – or increasing the number of required successes – without increasing the Challenge's level or experience while feeling confident balance is maintained, as PCs will have more abilities to negate or prevent failure.
The measure of fitness and health, healing surges determine how long a PC can remain active during a single day. They're a rough gauge of extraordinary action and activities. Healing surges are the default cost of failed Skill Challenges but could also be house ruled to contribute during a challenge.
Healing surges work nicely as a 4e equivalent of "drama points" or "plot points" from other game systems. These are a cashable and often non-renewable currency that can be spent for control over the story: having a contact, knowing a snitch, an extra feature in the room, etc. Action Points could also be used in a similar method, but keeping Action Points tied to actual actions (like the above house rule) seems more in line with the intent of the mechanic: you spend Action Points to do something extra.
Healing surges could be spent as "drama points" in one of two possible ways. The first is to unlock a skill not normally applicable for the Skill Challenge. In an earlier blog I advised players to "sell" their skills, thinking (read: BSing) a reason for a primary skill to be applicable. A healing surge could be used for this, if the logic is too much of a stretch or for the DM to limit the use of non-standard skills. In terms of flavour, the character exhausts, pushes, or stretches themselves doing something unusual. Therefore, it costs them a surge.
Healing surges could also be used to "boost" a skill. They can become trained in a skill until the start of their next turn at the cost of a surge. This might be limited to physical skills, but one could make an argument for it applying to any skill (straining to recall some obscure fact you once heard, which leaves you distracted later). This would be a great way to allow non-physical characters (the archetypal scrawny wizard) from not entirely being shut-out of physical or exploratory Skill Challenges.
The latter rule would also permit a reasonable increase of DCs for Skill Challenges, as there were possibly be fewer instances of a character being both untrained and untalented because they could choose to be trained at a cost.
This works nicely with 4e's design goal of always having an interesting choice every round. With so few skills and likely only one usable skill per type of Challenge, being able to gain a boost to a skill opens-up choices in the game.
I've mentioned how un-helpful magic items are out of combat before. The powers of a magic item will never come-up during a straight Skill Challenge and the properties only become applicable if they offer a static bonus to skills, which just makes the low DCs even more insignificant. Magic items outside of a fight are boring and ignore an important aspect of the game. Really, all aspects of the game other than combat.
Okay, this isn't exactly true. There's a L22 Ioun stone in AV1 that grants an auto-success on a check during a Skill Challenge, and a L19 ring that allows re-rolls and grants two successes after a milestone. It's a perfect example of how a magic item can play with the rules and limited mechanics of a Skill Challenge. And there's a ring and a ribbon (?) in AV2.
This stets-up the good and bad examples of Skill Challenge items. The Ioun stone and traveller's ring grant auto-successes through the use of a power. This is also possible through class powers, but only due to the low DCs of Skill Challenges and ease of Min/Maxing success. The star ruby ring grants extra successes if you've reached a milestone and still requires that initial success.
There's little that can be done about other magic items. These would have to be house rules on an item by item basis.
As a more generic house rule, it could be possible to spend magic powers for a bonus in Skill Challenges. This could overlap or replace any of the above house rules. Magic items gain more uses with milestones, to accommodate decreasing resources. So, working with the design intent for item powers, there could be a house rule that allows item powers to be used to help Skill Challenges despite lower resources. However, as stated earlier, there is no real resource management in Skill Challenges. Except managing successes and failures.
Given the three-strikes design of Skill Challenges, sometimes, especially with high Complexity challenges, three failures will slowly creep-up. When the party has two bad rolls at the start and the DM didn't add any options for mitigating or cancelling failure the Challenge becomes rigid. When one failure will end the Challenge no one is going to risk anything but their best skill or attempt creativity.
A possible house rule would be allowing PCs to burn a magic item daily power to not earn a third failure. This would still encourage items powers that improved the odds of successes to be used preferentially and encourage players to continue to be creative even with a couple failures, knowing if they botch there's a fallback. Alternatively, the magic item could delay failure, perhaps one round for each tier of the item. This allows it to be a short-duration fall-back but not a way for every player to stave-off failure endlessly