Ability Modifier: dexterity
Active/Passive: passive – this would seem like an active skill since you have to perform a key command, but the movement triggers a tumble (there isn’t actually a tumble roll for this) just as falling triggers a check (actually in DDO there is no roll, but there is for PnP
Class skill for: bard, monk, and rogue
Untrained use? Technically no, you can not use tumble if you are untrained. However, if you attempt to tumble (move while blocking) you will still move in little hop steps. It’s not as fancy but it is similar.
Armor check penalty? Yes
Feat modifiers: acrobatic +2
What it represents: your acrobatic skills and your ability to move with agility. In other words, your ability to perform an Olympic Games quality gymnastics floor routine.
How it affects gameplay: first and foremost, tumble reduces the amount of falling damage you take. The higher your tumble skill the higher you can fall without taking damage.
When blocking you can use the movement keys to tumble in various directions. Increasing your tumble skill allows you to tumble farther distances with each movement and can also change your movement animations into various rolls and tumbles.
Tumbling does not add to AC, but a skilled player can use tumbling to avoid being hit. At higher skill levels a tumble can cover some impressive distance quickly (even matching a character moving with haste).
Special considerations: you can use the tumble spell to increase your tumbling ability, however you will not gain the benefits of tumbling unless you have 1 full rank.
With the feat mobility you gain a +4 bonus to AC when tumbling but only if you have 1 full rank in tumble. This is regardless of what your total tumble skill modifier is so even a heavily armored tank with 1 rank in tumble and a negative modifier can gain the benefits of this AC boost.
The monk slow fall ability acts similar to tumble in reducing falling damage but also actually slows your fall speed until it maxes out as a full blown feather fall effect.
Who likes it: highly skilled twitch players, circus performers, and folks who can’t sit (their avatar) still.
How much should you have? Generally, I would tell anyone to throw 2 skill points into tumble to get 1 rank (or 1 point for those few who have it as a class skill) so they can gain some benefits from tumble, especially in combination with the spell.
A new player might find some benefit from a bit of tumble until they can acquire feather fall items or the spell. This will aid them in a few areas with long drops. However, veterans will simply use feather falling items as gear swaps for long falls (as a note you can swap these items in and out for long falls to fall faster – note you cannot do this by toggling a monk’s slowfall ability off and on).
Otherwise, there’s not a lot of benefit to investing in the tumble skill. A few players are skilled enough to effectively use tumble to dodge attacks, however this is a fairly advanced skill and even so is quite cumbersome.
Highly skilled tumblers are fun to watch though!
Use Magic Device (UMD)
Ability Modifier: charisma
Active/Passive: passive – the skill is part of the action to use the magical device
Class skill for: artificer, bard, and rogue
Untrained use? No – and that’s good cause you’d probably blow yourself up
Armor check penalty? No
Class, Racial and feat modifiers: artificers gain +2 to UMD to use various types of items as they level up (scrolls at level 1, wands at 3 and so on).
What it represents: your ability to use magical items (such as scrolls) that you would otherwise be unable to use (or would cause to explode if you tried).
How it affects gameplay: there are 2 uses for UMD. The first is to use restricted items that you don’t qualify for. These are either alignment restrictions or racial restrictions. Restrictions do not require a roll to bypass but are instead a straight comparison to your modifier. Alignment restrictions are pretty consistent usually a UMD of 20. Using UMD to use an alignment restricted item will not negate the negative level that you may get for using an item that is of an opposing alignment. Racial restrictions reduce the minimum level of an item by 2 and their UMD is based off of the level and type of item thus giving them a greater range. Items can have both restrictions and will require you to pass both restrictions individually, either by meeting them or using UMD to bypass them. The needed UMD for restrictive items is listed in their descriptions and some restrictive items cannot be bypassed by UMD while other alignment based items have no UMD needed (but still may impose a negative level).
The second use of UMD is to use a wand or scroll. As with restrictive items the needed UMD is in the item description but this time a skill check roll is made giving you a variability of 20 (1 is not an automatic fail). The UMD score needed is determined by the level of the spell and a charge/scroll is used whether or not you succeed or fail (remember that you may also need to make a concentration check if you get hit). Wand and scroll DCs are usually 18 + twice the spell level.
Special considerations: you can meet requirements for using scrolls and wands by meeting the class and level requirements listed in the item descriptions. Wands typically only require 1 level of a class that can cast the spell. Scrolls require the level and class able to cast the spell normally, but characters just shy of this can make a caster level check to use a scroll of slightly higher level.
Arcane scrolls are subject to arcane spell failure if you are wearing armor.
Some artificer scrolls require a higher DC.
The standard UMD benchmark to hit is 39 which lets you use heal scrolls without fail (DC of 40 – reachable with a 39 because you roll at least a 1). A lower mark to hit is 20 so you can use some of the alignment restricted items (pure good being the most useful).
Who likes it: everyone. Even if you don’t have it, that guy who has saved your party a few times by using UMD to raise the party. Also, the technically challenged.
How much should you have? Go big or go home. If you are taking UMD then get as much as you can and find some items you can swap in to boost yourself to UMD mode. It might mean some of your other capabilities suffer, but you are probably using UMD to keep yourself or others alive so that likely takes precedence. UMD characters that can swing in to bolster party healing can easily be the difference in a quest and raid being successful or a failure. I have not only swung in to heal with my UMD toons but I have done raids primary healing with my artificer. Rogues, bards, and artificers should not only get UMD, but they should also consider taking at least a few levels of scroll mastery to augment their heal scrolling. If you are going to be using UMD in this manner, you want to get to mid 30s.
If you just want to be able to raise dead, well then you should be going for heal scrolls – it’s only 1 spell level difference.
If you can’t at least maintain a UMD of 20 to use restrictive gear then there is no point in taking UMD. Anything restrictive less than 20 isn’t worth using at higher levels.