Concentration Combinations

[Mistwell]

I just noticed three feats that have some synergy:

Steady Concentration (Races of Stone) lets you take 10 on centration checks any time.

Mobile Spellcasting (Complete adventurer) lets you move and cast as a standard action if you make a high concentration check (DC 20 + Spell level), and you can even avoid AOO for casting if you make an even higher concentration check (+5 to above DC).

Extraordinary Concentration (Complete Adventurer) lets you maintain concentration on a spell as a move action (DC 25 + Spell Level) or even as a swift action if you make a high enough concentration check (+10 to above DC).

No, I am not saying Mobile Spellcasting and Extraordinary Concentration are somehow used together at the same time, just that a build focused on concentration might want both feats for different uses.

Has anyone created a build focused on concentration, with maxed concentration ranks and a good constitution and maybe skill focus: Concentration?

An item that would help with this concept is the Tunic of Steady Spellcasting (Complete Adventurer) which grants a +5 competence bonus to concentration checks.

 

[xen_xheng]

If I remember correctly, there is an item that gives +10 to concentration in the Expanded Psionic Handbook (Third Eye of something)

 

[Mistwell]

So I took a quick review of PHB spells with concentration as a duration element. Most are illusions (though a few cool ones are not, like fire wall and swarm of insects).

So, given that, the best character for this concept is probably a gnome illusionist or gnome bard, since gnomes get a +1 to illusion spells. They also get a +2 Con for a -2 strength, also good for concentration checks. The perfect fit. I might consider a Whisper Gnome (Races of Stone) instead, as they have a combined +8 to hide, 30 foot movement, +2 Dex and +2 Con for -2 Str and -2 Chr, and darkvision. No +1 to illusions, but probably still worth it.

A Gnome Illusionist that takes the first replacement level for such gnomes from the Races of Stone reduces the level of many illusion spells that have concentrcan as a duration element ( Silent Image as a 0-level spell, Minor Image as a 1st level spell, major image as a second level spell, etc..). Probably a good option. The fifth level replacement gives extended illusions (double duration), which also adds 1d4 rounds to any concentration-only spell. Also a pretty good option, unless you need the extra 5th level metamagic feat (to get into a prestige class like, say, Shadow Adept).

So, by 12th level (which is when you get Extraordinary Concentration), you will have selected Steady Concentration (Races of Stone), Mobile Spellcasting (Complete adventurer), Extraordinary Concentration (Complete Adventurer), Skill Focus: Concentration (which might be overkill, particularly if you have a high Consitution, in which case I would take Shadow Magic from Player's Guide to Faren for another +1 DC to illusions and +1 SRP to illusions and access to the Shadow Adept prestige class from Player's Guide to Faerun), and probably Spell Focus: Illusions. You have 15 ranks in Concentration, a Tunic of Steady Spellcasting (Complete Adventurer), and an 18 Constituion (not that hard given the +2 Con for being a gnome and 3 chances to increase your Con from levels and can afford a +2 item if you want it).

Take 10 (Extraordinary Concentration) + 3 (Skill focus) + 15 (ranks) + 5 (Tunic) + 4 (Con Bonus) = 37. That's enough to maintain concentration on a Major Image (2nd level spell with the gnome illusionist replacement level) as a free action (which requires a Concentration check of 25 + 2 (spell level) + 10 (free action instead of move action) = 37). You can keep your major image (which has full sound, smell, thermal, and movement within an 880 foot range) indefinitely while you are awake, making it react to anything that strikes it appropriately, and do whatever you want it to do.

If you can get your concentration check up a bit higher, or increase your Con, or a combination of those two, or just wait a few levels, you can maintain a Mislead spell all day long (for those who don't recall that spell, it turns you invisible as improved invisibility plus makes a replica illusion of you in your place at the same instant as a major illusion that then walks and talks and acts like you can moves independant of you). Why risk your own neck when you can risk the neck of your illusionary double?

You can also move and cast as a single standard action, while still avoiding AOOs for casting defensively. It's a concentration check of 25 + spell level, and since you already have a 37, you can cast a spell of any level while moving.

I think taking some, or all, of the levels of Shadowcraft Mage (Race of Stone) would also be useful for this build. That prestige class surrounds you in constant concealment (up to 40%), lets you cast all illusions silently without a level increase, extends the duration of illusions by x2, lets you convert your Image spells (silent, minor, major, etc...) into shadow evocations or shadow conjuations (creation or summon) that are semi-real and that increasingly more real at 5th level.

Wow, this would be one annoying little bugger. Usually invisible, but appearing to be visible through illusions of him, silently casting illusionary evocations and conjuations (at +1 DC from Spell Focus, since they are still illusions), that are powerful and hurt you even if you make your will save, scampering around hidden while casting simultaneously (so he can double move and still cast in the same round), with multiple llusions of anything he can think of that just DON'T go away EVER until you knock him out (which means catching him first - fairly hard to do).

 

[Shin Okada]

Complete Adventurer has a cleric spell called Divine Insight. Basically, it gives insight bonus of 5+caster level to one skill check. The duration is 1hour/level and the caster can discharge to use it as an immediate action, once per casting. My PC's cohort is a 7th-level Rogue/Cleric/Shadowbane Stalker. He has Steady Concentration and almost always using this spell. Usually, he uses that skill bonus for disabling magic traps. But in emergency, he can automatically make success in one very difficult Concentration skill check (say, DC 30+).

In our campaign, both PCs and enemies use Mordenkainen's Buzzing Bee spell (from Miniatures Handbook) intensively. So high Concentration skill is important.

Edit : It is an immediate acition, not a swift action.