Well congratulate me. I now have a breeding pair of dragons AND hydras. The only problem is they won't breed.
I've tried everything i could find on the subject. I even removed the [FANCIFUL] tag thinking it may be blocking egg fertilization. Still watching the animal trainer but they forget training very slowly so im very sure they aren't dieing. No trainer is assigned to the females and won't be unless they revert to semi-wild. BTW: dragons must have a very good memory because while the hydra lost 2 levels sitting on the nest, the dragon did not forget.
Another oddity is my hydra eggs do not show up on the kitchen list and dwarves will haul them if i don't forbid or lock the room.
This is what i've added to the hydra:
[LAYS_EGGS]
[EGG_MATERIAL:LOCAL_CREATURE_MAT:EGGSHELL:SOLID]
[EGG_MATERIAL:LOCAL_CREATURE_MAT:EGG_WHITE:LIQUID]
[EGG_MATERIAL:LOCAL_CREATURE_MAT:EGG_YOLK:LIQUID]
[EGG_SIZE:6100]
[CLUTCH_SIZE:1:3]
[CHILD:1]
[GENERAL_CHILD_NAME:hydra child:hydra children]
She lays but they don't hatch and the eggs get hauled.
Another sidenote, i think removing the [MEGABEAST] and [FANCIFUL] tags may have triggered an Age of Legends. I scumsaved since i believe it was due to the missing MEGABEASTs.