Stopped playing dota for my HSC but i gotta say that morphling is the ultimate hero =] i go beyond god like most games with morphling.
Dagon on Gondar is just absoluetly fked ... he doesn't need mana, he need attack speed, damage and MS (good generic build would be - threads, sny first up then any damage/attack speed items such as butterfly, maybe get a travels in late game)
and a very very good item build for 2 head dragon would be eul's first up, then meknsm then dagon
y eul's? first, you cyclone them, then u ulti them while they in cyclone, when they come down, you icy path them ( loads and loads of damage =]) and then you duel breath them (if not dead yet then they should be on red hp) and then you dagon if u got it, otherwise just run up and hit them a few times (duel breath would slow them) if still not dead (ie, damn centaur or omniknight) then u duel breath them again =D