Which skills will actually be useful in DDO, and which are just "roleplaying flavor"? Here are brief comments on how often you can actually use each skill, and how important it is to succeed.
In general, roles need skills in this order of importance:
- Bards: Perform and Use Magic Device
- Monk: Concentration
- Rogues: Search, Disable Device, Open Lock, Use Magic Device, and Spot (except Elves and Drows)
- Spellcasters: Spellcraft and Concentration (unless they plan on using Quicken Spell at all times)
- Tanks: Intimidate
- Healers: Heal and Concentration
- Warforged: Repair for self-healing with spells
- Everyone: Jump and Balance
If you play a combination of roles (e.g. Rogue-Melee-Bard), you should determine the order of importance based on the order of this list (e.g. Bard skills before Rogue skills before Melee skills).
- Balance (DEX): If you are knocked down, not only is the player considered prone, which is a common threat for melee fighters and especially dangerous for spellcasters if they happen to get into melee range, but they also may not act normally, effectively rendering them little more than hardy obstacles. While a high Balance score does not prevent a character from being knocked down, it allows to recover and get up sooner.
- Concentration (CON): Receiving damage while casting can interrupt the spell unless a successful concentration check against the damage received is made. This makes concentration important for combat-spellcasters, especially healers, unless you primarily use instant spells or Quicken Spell. But keep in mind that all scrolls and some spells may not be quickened. For a Monk, Concentration is the most important skill, as it determines not only their stable ki level, but also how quickly it decays.
- Haggle (CHA): Allows you to negotiate better prices with vendors. Each point in Haggle will increase the price of the items you sell by 0.25%. As money is primarily generated through the Auction House (where Haggle does not influence prices), this skill is of limited use. Many players level a specialized "Haggle-bot" or use those of friends or guild-mates.
- Hide (DEX): Hide determines how easily you can be found by enemies. With Update 19, enemies are always searching for you. An enemy's Spot check in a visual arc in front of them determines if you will be spotted. Hide opposes their Spot check, but only briefly as enemy Spot bonuses increase as you get closer. As most groups do not wait for stealthers and just attack whatever comes into their path, this is of limited use in group combat (you can still stealth mid-combat to use special attacks), but might be very useful for solo play or stealthier-groups that prefer to avoid enemies. An Invisibility spell makes you visually undetectable and therefore completely replaces Hide, unless enemies use True Seeing or See Invisibility effects.
- Jump (STR): As enemies are actually blocking your path, jumping can be very helpful to maneuver in close-combat. As some enemies can be very large, a high Jump skill is recommended for most melee characters. In addition many dungeons contain platform-style puzzles, a high Jump skill can make those much easier. Some dungeons even contain secret areas, that characters are unable to reach without a specific Jump skill. Those puzzles however can often be solved by using a Jump spell or an appropriate potion, however a high Jump skill can make you feel much less clumsy. Depending on how well you can take incoming damage, a Jump skill of at least 10 is recommended, go higher if you want to make sure that you can escape from all combat situations.
- Listen (WIS): This skill has a very limited use. It allows you to detect stealthed/invisible enemies, but it displays only a red dot at the feet of those enemies, which can be missed easily, while a good spot skill allows you to see those enemies as black, transparent shadows instead. Listen is the only skill able to detect enemies under the influence of an Invisibility effect, this can however be countered as well by a True Seeing or See Invisibility spell.
- Move Silently (DEX): This skill determines how easily you are detected by enemies while sneaking. In contrast to Hide, enemies must however make a Listen check (instead of Spot) to locate your position. If you plan on playing a stealthier character, a high Move Silently skill is strongly encouraged. In addition if you plan on using Invisibility a lot, you should invest into Move Silently as well, as Invisibility only renders you invisible, but not in-audible. Some enemies (e.g. vermin, earth elementals) have the ability tremor sense, which makes it close to impossible to sneak past them.
- Spellcraft (INT): This skill adds 1 point of Spell Power to Acid, Cold, Electric, Fire, Force and Light spells. It is essential for all casters who want to increase their damage to keep it maxed.
- Spot (WIS): Spot allows to detect traps and secret doors as well as sneaking enemies. However as the location of traps are usually fixed, Spot becomes much less useful if someone in your group can just remember/spoil those locations, and hidden enemies are rarely an issue as they reveal themselves on attack. Yet Spot can be helpful for new players or inexperienced groups, or if you run a Quest with random trap placement. With Update 19 (Drow) Elves can spend points on the Enhancement Nothing Is Hidden that allows them to automatically perform Search checks if their Spot skill is sufficient to spot the trap.
- Swim (STR): This skill is generally considered useless, as items or spells that enable infinite water-breathing are already available at level 3. The only benefit of a high Swim skill is that you are able to swim (and for some reason fly) faster, which, while handy in its own right, is perhaps most useful in one section of "The Crucible." and "The Reaver's Fate."
- Tumble (DEX): While visually fun, this skill offers very little to most non-Evasion classes. The first advantage is to reduce falling damage but that is often taken care of by Feather-falling items. The second advantage is to allow greater mobility while shield blocking, and is the only real use for the skill. Many tanks try to toss a point or two in it in order to be able to tumble while shield blocking. A high Tumble will allow somersaults and backflips for quick escapes. In the Shadowdancer and Grandmaster of Flowers Epic Destinies, a very high Tumble improves their special abilities to literally tumble through an enemy. That can be very beneficial in "stick and move" fighting in Epic quests where character damage is much greater.
- Use Magic Device (CHA): An incredibly useful skill if the player can reach high scores, it allows the character to use Heal (for fleshies) or Reconstruct scrolls (for warforged) to self-heal himself or herself. Other useful items to use via UMD are Raise Dead scrolls, Resurrection scrolls, Fire Shield scrolls, Restoration scrolls and Stoneskin wands. It can also be used to circumvent alignment restrictions and race restrictions. This however usually requires a high UMD skill, which makes it only useful for those, that consider UMD a class-skill. Half-elves might find this skill of lesser use, if they have a dilettante feat, that allows them to use the items in question without any check (e.g. Cleric dilettante feat allows the use of healing wands without checks).
- Bluff (CHA): In combat this skills can be used to reduce your threat and allows to make sneak attacks on an enemy briefly, which makes it very valuable for Rogues and other squishy classes, even though the short animation forces you to interrupt damage dealing for a moment. In addition it can be used to pull single targets from a pack of monsters. Even though the monster will become aggressive 1 second after he reaches the bluffer's pulling location, and will go after the bluffer, careful kiting and intimidation timing will allow to pull one mob to the party at a time, which can be useful when there's a lack of crowd control. In addition several quests allow to solve puzzles or gain extra treasure using this skill in conversation.
- Diplomacy (CHA): Diplomacy is used to shed aggro to a nearby ally. While potentially useful, it's a tool to be used carefully as it can be worse, sometimes, to send the aggro to an ally than to keep it on yourself. Diplomacy is particularly useful to squishy characters. Players may also appreciate higher points to this skill for more favorable options in some quest dialogues with NPCs. Diplomacy is also used for some special Epic Destiny abilities.
- Disable Device (INT): As traps on higher difficulty levels tend to be deadly, this skill is often highly valued by Rogues and Artificers. As those traps as well have a high DC and a failure can make further attempts to disable them impossible, it is recommended to not only max-out this skill, but Search as well to be able to actually find those traps.
- Heal (WIS): Every point of Heal grants 1 point of Positive and Negative Spell Power. It's a must have for healers to increase their healing potential and it may be worth taking for Pale Masters Wizards to increase their Negative Spell Power (even if for them is a cross-class skill). Other than that the active use of the Heal skill is generally considered pointless, as even the most minor healing spell does the same and is usually easier to use. The quest "Outbreak" benefits from a higher Heal score for an optional objective.
- Intimidate (CHA): The art of holding aggro with Intimidate is often known as Intimitaking and is the main ability to keep enemies on the tank. Although tanks can get abilities to increase their threat, a defensive-focused tank can almost never out-threat an offensive damage dealer, leaving this skill as the only chance to control aggro. Especially since those damage dealers tend to not value threat-reduction abilities too much as they don't deal any damage...
- Open Lock (DEX): While this skill is almost never required to complete a mission, it often allows to gain extra treasure or rest shrines. Open Lock has often a lower DC than Disable Device or Search checks, but still requires a fairly high level for higher difficulty locks. Although there are skills and spells that imitate the use of Open Lock, those can often only open simple and medium difficulty locks, making this skill essential if you want to make sure that you can get all the loot.
- Perform (CHA): As this skill allows a Bard to learn new songs (depending on the points spent on this skill, NOT the total mod) and as well determines the DCs of many of his abilities, it is a must for all bards. In addition this skills grants 1 point of Sonic Spell Power for every point of Perform you have.
- Repair (INT): Every point of Repair grants 1 point of Repair and Rust Spell Power. Warforged casters or casters who want to increase their ability to heal warforged should take it. As for the rest it's identical to Heal, but applying only to warforged.
- Search (INT): As traps on higher difficulty levels tend to be deadly, this skill is often highly valued by Rogues and Artificers. As those traps as well have a high DC and a failure makes it impossible to even try to disable them, it is recommended to not only max-out this skill, but Disable Device as well to be able to disable those traps afterwards. In addition this skills allows a character to find secret doors with a high DC level, while those with a lower DC can usually be found by the Detect Secret Doors spell.