If you have speed, be that the Anklet or journeyman treads, then you can really nullify Reg. As a Reg player i know that the speed of another player scares me more then what HP they can take from me...cause if they catch me no matter what (until late game) i am dead, no two ways about it.
Want to offset Reg, get Journeyman Treads if you can.
As for a whole team of them amte, that is just bad luck, any all DG team is going to be really powerful and hard to defend against.
Even if you are not fighting him you have to now be twice as careful when battleing other Demigods. When you life hits half you have to run for fear of being Sniped from halfway across the map. Just by him being on the other team it changes the way the game is played. I do not feel one Demigod should have the ability to effect the game on this kind of level.
sounds like your not putting enough points into your health mate. The snipe is worth at max ~1100. So unless your not putting any points or gold into improving your health then there shouldn't be an issue.
I personally look to have ~4K HP.....(i want to withstand two spit's if i can) if your playing with starting health, then your gonna get trounced mate.