So. I suspect there's not been much interest in Spirit Bond compared to the WSD stuff. But I was curious.
Went out and tested a bunch. This was all made far more confusing by the fact that battlemod currently suppresses the log notifications about the DRG taking dmg via Spirit Bond. So I had no idea there even was a log message for... most of my testing time. Needs an update.
Anyway. Spirit Bond takes the wyvern's post pet DT dmg taken, and splits it 50/50 with the DRG. This happens before Steady wing is applied though, so you can take dmg while your wyvern is getting hit for 0.
Further, the player's DT does not affect this dmg taken at all. It can be mitigated with stoneskin, so cureskin can help. Phalanx might work as well, but I haven't tried it.
Overall, I'm a bit concerned about the actual usefulness of this. It seems like a pretty good way to die to an aoe that you would have survived normally. Now, funneling some of the dmg to the DRG, who can be cured by mages, where the wyvern can't makes a sort of sense. But taking basically double dmg from AoE's seems really dangerous. If player DT worked on the DRG dmg taken then it's be a lot more appealing
My favorite example here...
In this example, my wyvern had 76 PDT. 40 base, 25 from collar+2 and 11 from ptero legs+3.
10,000*.24=2400 /2=1200.
Now as you can see, then numbers there are slightly off. I took 1210 not 1200. It seems like the wyvern base 40% is actually a tiny bit less that 40%, or some kinda weird rounding is going on. This can also be seen without Spirit Bond up, just from the wyvern taking 2k needles.
I have some data from before I realized there was a log message for the drg's spirit bond dmg, so I'll go ahead and post that in case anyone wants to try to figure out the wyvern's exact /256 DT.
And I'm not even going to try to make this pretty
Code
*Note that the dragoon field here is the actual direct dmg from the needles move, not the spirit bond dmg. Since I didn't realize that had it's own log message at first.
Needles targets Dragoon Wyvern Bond? Martel PDT WPDT
2000 2 1000 601 No 0 40
4000 2 2000 1203 No 0 40
2000 2 1000 301 yes 0 40
4000 2 2000 602 yes 0 40
2000 2 511 172 yes 50 65
4000 2 1023 344 yes 50 65
2000 2 500 172 yes 60 65
4000 2 1000 344 yes 60 65