A few of my friends and I dusted off our 3.0/3.5 books for a replay of my epic-powered campaign. This time around, I decided to allow the gesalt rule and we instantly ran into a problem- a player added monk levels to a blue dragon.
Since I cannot find clear answers elsewhere, I ask: what will this character's damage progression look like? Does the monk's unarmed damage replace the dragon's typical size-based damage?
According to Gestalt rules, you take the best of the two and don't stack them. The players takes the one that gives the best damage. Note: Some things do stack like feats and certain natural attacks. If the dragon's damage explicitly states that it stacks, then it does, otherwise only let the player take the best of the two.
Gestalt characters can be and are very powerful. Use extreme caution in any campaign that has gestalt characters.
So I need to adjust the monk's unarmed damage for the dragon's size increases, and use whichever value is better... I figured this would be the case and I strongly suspect the monk's damage will always outclass the dragon's base damage. This is one minor headache I am not sure I want to deal with 
Yes, if the monk gets a size boost from his dragon class, then he would compare the dragon's damage to that of the monk's at the new size. Monks do gain extra damage for being larger just as larger sized weapons do. Yes, I believe, the Monk damage would be superior. Keep in mind that the Monk would not be able to Flurry and still use a dragon's breath weapon in the same round as Flurry of Blows is a full round action.
Given that there may be feats or templates that might allow the player to stack some of the damage, this type of issue is why gestalting anything but the base classes is a bad idea. Even then, gestalt isn't for the faint of heart. For example, a plain Druid/Monk is down right devastating-- Natural attacks + Monk attacks and Druid spells + Shapeshifting = a collosal game ballance challenge.
I'm not sure what you two are talking about, but a dragon does not get improved unarmed damage.
A dragon monk deals unarmed damage based off of size and the monks unarmed damage tables. It also happens to have 1 Bite 2 Claws 2 Wings 1 Tail Slap 1 Crush 1 Tail Sweep that it can make attacks with that deal damage based off of the dragon natural weapon damage table. Those two things don't interact in any way.
To explain. A level 8 Large dragon monk has the following natural attacks.
- 1 Unarmed Strike for 2d8 damage
- 1 Bite for 2d6
- 2 Claws for 1d8
- 2 Wings for 1d6
- 1 tail slap for 2d8
It can make a few attacks.
- Standard attack - Any of those attacks at +6 to hit for XdY damage.
- Full Attack - Unarmed Strike at +6 for 2d8, Unarmed Strike at +1 for 2d8, Bite at +1 for 2d6, 2 Claws at +1 for 1d8, 2 Wings at +1 for 1d6 and a tail slap at +1 for 2d8.
- Flurry - Unarmed at +5 for 2d8, Unarmed at +5 for 2d8 and Unarmed at +0 for 2d8.
Krusk, I believe he is talking about a situation where a monster type becomes a class. Savage Species has some as well as there is the Dragon Desciple class where the character gets increases to natural damage as a blue dragon does (to a point). The OP was asking how the damage would be if such a class if gestalted with the Monk Class. I was also explaining how gestsalt would work in that case and the fact, that by PHB 2 rules, gestalt is for core classes only so by adding the dragon class is already house rule teritory.
Yes, if the character is a blue dragon as a race (and not a benefit of a class) and was just a Monk (not gestalted with any other class) you are 100% right.
Notice in my first response, one simply takes the best of the damages and doesn't stack them, just as you show on your chart.
Thats actually fine to do it that way too. The Dragon racial class from savage species also doesn't grant improved unarmed strike, it grants natural attacks.