Greetings!
This is the player behind abysia speaking so no roleplaying involved.
What you did can be called cowardice especially if coming from the self-declared 'forces of good' but it was COMPLETELY a legit tactic both as a roleplay thing (abysia is, in fact , an evil nation:P) and as a diplomatic thing (you formed an alliance and attacked a nation your percieved as a threat).
So absolutely no whinings or ill-feeling on my part it's just the way the game plays :-)
However you couldn't expect me to go down without a fight and making you pay DEARLY for your invasion right??
Snd so now you have a fight! You may very well likely win (even with r'ylen defensive support) but who knows at least we'll have some fun :-)
As to explain r'yleh help well i actually expected it because of a precedent.
I was in very very good term with Ulm and r'yleh and tried hard for many turns to make them like each other and bring them together in a war front.
In the end, for a mistake i think, ulm invaded r'yleh so i could standby and do nothing (possibly losing 2 friends and being completely surrended by a very large and powerful nation) or pick one... i picked the one in my view was the invaded one and stook with him in the war.
Unfortunatly your 'alliance' had good intelligence and decided to attack me when most of my forces were away so now i can't committ with Ulm! i also tried to convince Ulm (and r'yleh both) to make peace well it didn't work :-)
Now i'm in a very interesting fight with 2 land nation attacking me in the west, your seraph in my backyard and ulm on the north.. interesting isn't it?
P.S.
Edit for blood magic-> it is of course a very good school of magic BUT though being powerful (ask marignon and arco:P) it's not invincible.
This is my first game playing medium abysia (even on sp..) and first mp game so i'm a very far away to master it.. guess i'll learn along the way as we are all doing !