well...it's well known fact. UB cant win good Erebus or Sedna in 1v1 game. I hope they'll fix it but many ppl here on forum says that it's not 1v1 game and if it's not balanced in 1v1 dont mean that it's not balanced in teamplay. I dont think so and hope they'll make a balance in 1v1 game any DG can win any other DG. At that moment i dont know any build or tactics for UB to win good Erebus with Minions build or good Sedna. I was playing with Erebus yesterday. And he uses something like horn as a favor so his minions gets huge HP regen so even me+towers cant kill them. So they just easy destroys all the towers and win the game.

Sorry for bad English

It's actually possible to beat good Sedna with UB (UB damage output is much bigger than Sednas Heal + Regen, you just have to stack HP and carry potions with you, as well as you need to start getting the towers on lvl 4 with spit).

But yeah - it's virtually impossible to do anything with UB against Erebus.

The only way that MAY work is huge ammount of AOE damage (Post Mortem + Ooze) and Parasite egg at some point (There's no way Erebus can avoid u totally, so there'll be moment when you can hit him at least 2-3 times before he swarms away. I actually beated few good Erebuses with that kind of build, but that takes HUGE ammount of patience, cap-locking (Because it's really hard to maintain flag control against minion Erebus, who is virtually in 2 places at the same time) and accurate play.

Just going to add that I find that Sedna has difficulties defeating an Ooze UB.  I have one damage skill against him and have to spam it to graze his health/armor, sinch autoattacking comes in so slowly.

I don't view 1v1 as an intended gametype, and the game isn't balanced for it anyway. Can you play it? Sure. Consider that there's 8 maps - 1 2v2, 2 3v3, 2 4v4, 3 5v5 maps and you can see that the intended team size is primarily 3 - 5 players per team. Personally I think the game doesn't play well enough until 3v3+ but that's my opinion.

Sedna is absolutely sucker in 2v2 usually There're no OP demis in any game except maybe UB and Ereb in 1v1