One of my better Topic Titles if I do say so myself..

My friend is making a Detective character, and like a good Detective, he has a good eye. (Perception Rating 6 with Visual Specialization, Reaction 6, Intuition 5.) He also has the Perceptive Defender Quality which at the moment, looks like it might be giving him a character that is a little overpowered, but which also totally fits the character concept, and I have to admit, looks like it would be fun to play, but might be a pain in the arse to GM.

So with Perceptive Defender Quality...

Character has Perception 6 (Visual +2). Does this give character 8 Dice to add to Intuition and Reaction for Full Defense?

Cybereyes give +3 to Mental Limit for Visual Perception tests, and add +3 Dice to Visual Perception when using Wireless. Does this raise the Full Defense Limit by 3 and add 3 dice when using Wireless?

Character has Attention Co-Processor (+1 to Limit to Perception tests and adds 1 die to Perception when using Wireless.) and Synch Transgenics (+1 to Perception) Is this cumulative as well to Full Defense?

If you answered yes to all the above... this would give character a Full Defense pool of 20 (24 when using wireless Ware.) With a Limit of 12 (Mental Limit + Cybereyes Rating + Attention Co-Processor.)

This is where things could get a bit ridiculous...

If character gets Reatk treatment (+2 to Ranged/Melee defense tests) combined with either Novacoke (+2 Dice to Full Defense) or Pysche (+1 Dice, +1 Limit) to Full Defense when using Perceptive Defender....

....character would get a Full Defense dice pool of 28 and have a Limit of 12. (Novacoke)
.... Full Defense dice pool of 27, Limit 13 (Psyche)

Also.. The Novacoke would totally fit for a Sherlock Holmes type detective character..

While 27 to 28 Dice for Full Defense is not the craziest thing I've ever seen on a character. A starting character could get a 24+ Dice Pool for Full Defense without taking Perceptive Defender Quality (A starting Adept, with Combat Sense 6, could easily get a 24+ Dice Pool for just regular Defense), it definitely is very close to being a bit overpowered and it could cause me some headaches as a GM..

Any thoughts or suggestions on what I should do, would be much appreciated..

Thanks.

I forgot Perceptive Quality.. another 1 to 2 Dice..

This doesn't happen in a vacuum.

How does it relate to the other characters in the game?
Are they also potentially gifted with very high dice pools, just in other areas?
Are they at significantly lower DP levels?

Are you averse to ramping up the power level?
Do you want to have a more "sensible" (without passing judgement) street level game?

Summarizing:
The DP itself doesn't tell me anything about if you should allow it.

And for the record: I also think that it fits such a character archetype very well.

The other player that I know for sure, is a Magician with a 16 Dice Pool for Manipulation Spells and a high Dice Pool for Binding Earth Spirits.

The other player is probably going to play a Technomancer or Rigger. No clue what stats are yet.

Not adverse to bumping up the power level. I always try to make the players first run easily survivatry, and unless the players do something Really stupid, they should easily be able to finish the first run.

Does it really matter if he has a high full defense pool? Going full defense means you don't get to do anything else. So while he is dodging around he isn't attacking or doing anything else to end the fight beyond maybe running away. So does that matter?
Also, what is the lost opportunity cost of him doing this? That is, what is he now weaker at after investing in these abilities. What won't he be able to do that might be useful?
In addition to the other characters you shoul think about what this character can't do now. One trick ponies frequently end up being a major liability to the team if they have over specialized. So don't just worry about the the high dice pool in one area but also just what that means for the character over all.

You should read up on the Combat Rules...

Full Defense is an Interrupt Action. It can be performed any time during the turn, but only if you have at least 10 Initiative, and only if character is not surprised. It lasts the entire Combat Turn, you lose 10 to your Initiative Score, but as long as you have 11 or more, you still can make an Attack that Turn.

.. this character has an Initiative Attribute of 12 + 1D6. Even If he rolls a 1 for Initiative, he still gets an Initiative Score of 13.

...So let's say character is attacked by two wired goons who get 24 and 25 for their Initiative, Character can go on Full Defense right at start of Turn, which would lower his Initiative Score to 3.
Goon (25) would go first. If he attacks, he would Roll Weapon Skill + Linked Attribute vs 28 dice.

If the next Goon attacks as well, he would Roll the same vs 27 (-1 to defense for defending against a previous attack.)

Then character would have a turn. If he attacks with Pistol, he has 16 dice, +/- modifiers, to roll to attack one of the goons. He would more than likely be able to at least injure one of them with 16 dice to throw for an attack.

The goons could attack another two times each before the Combat Turn ends, with each attack reducing the Full Defense dice pool by 1, but the NPCs attacks would still have to beat 23 to 26 dice, and if they are attacking with anything but Single Shot Firearms, they are facing cumulative recoil penalties.

Even if NPCs had 12 Dice to roll for attacks, my money would be on Detective coming out victorious.

He'll still be susceptible to spells and all kinds of other nastiness. Get creative. If the whole group is somewhat optimized, don't forbid it outright.
If the group is not on the same level, have a talk with either the high outliers or the low ones on what they expect from the game and meet somewhere in the middle.

If it makes you uncomfortable, talk to the player in question and tell him that you feel his optimization makes you fear that you may under-challenge him while over-challenging his fellow players if you tailor your encounters to a group average.

It's not a matter of dice pools, it's a matter of expectations for the game.

Personally, I would only allow the base or augmented skill to be used, per the quality - no specializations or dice pool bonuses.

Your making a defense check not a perception check.

I would only count bonuses that affected all perception not just one sense, and only the ones that added to the skill not ones that added to the check.

For limits it specifically states that it's mental limit not perception test limit.

I use Glyph's approach - skill only, no specializations or enhancement - and it works well. Adding 6 dice to a defense test is by no means game-breaking.

Perceptive Defender allowing a player to add 6 dice is relatively modest compared to Too Pretty to Hit adding 8 dice for the Elven face or Agile Defender adding 10 dice to the heavily augmented samurai. If other players had those qualities then I would start to loosen up my restriction on additional modifiers for Perceptive Defender. I'd probably let the Perceptive quality count, and the Enhanced Perception adept power. I'd probably give the Attention Co-Processor a pass too.

Your not adding 6 dice dice even at char creation. It replaces the willpower attribute. So depending on the character's willpower is how many dice your adding.

In the long run it helps more because it is a skill hence easyer to incress with a higher cap.

I stand by my statement. If adding 6 dice isn't game breaking then neither is adding 1-5 dice.

And, yes, Perception has a higher cap because it is a skill. If someone wants to spend 114 karma advancing their Perception from 6 to 12 then hats off to them; they can have their additional full defense dice. Their GM can hit them with a Direct spell or an AoE attack instead.

I would allow it with Glyph and Tecumseh's caveats.

There are more threats than bullets out there if you feel you need to jeopardize his health.

As for "losing an action" vs. "losing 10 to your Initiative Score": it is the same thing. Yes, a person who has 11 Init Score and takes Full Defense still gets an attack...but that is INSTEAD of taking 2 attacks (once at 11 and once at 1).

That is an example of Opportunity Cost (as is all the resources he spent to get the high perception and positive quality). You will get to experience that same Opportunity Cost when your grunts shoot at the other characters instead of him (because you cannot hit him).

It sounds like he found a clever way to "tank" but that comes with all of the other repercussions of trying to tank in a tabletop RPG.