Riddle time

Easy Mode is to ask the bird on the left which way the bird on the right will tell me if I asked the bird which door is the way to heaven.
Go the opposite way.

Hard mode: If there was someone who always said the exact opposite thing you would say, which door would the person direct me to to lead me to heaven?
Go the opposite way.

God mode: (Assuming liars don't go to heaven, and that the birds are still invisible.) Which door did you come out of?
Go the way they tell you.

"Give me your throne or I'll slash your throat with this glass I pre-smashed!"

Mantis is a fag. Riddle solved.

Solved every mode.

god slayer mode: by becoming god the curse is broken simultaneously

God slayer mode didn't work, if you asked the lying bird it will lie to you and will tell you he came out from heaven's door

EDIT:
In GOD slayer mode I suggested sticking your ear in a door, if you hear scremings and mournings that might be the door to hell

That's the point. He came out of the hell door, but since he HAS to lie, he says the heaven door.

Might i ask if the door's are soundproof?

You asked which door, and you're assuming they would point to the door they came from but they could simply just make a statement of which door they came through without pointing to which one is which.

With what you said they'll both say that they came from the heaven door so how do you distinguish the truth?
Nevermind what i wrote it's 4:20 am and i understood it after i read Loner's comment.

they might of not came from any of the doors as well

Riddle has too many variables for it to be worked out, because most answers will have loop holes.

This is a mindfuck, especially at 3:29am. I really need to go to sleep.

godslayer mode: ROW ROW FIGHT DA POWAH!

Do the birds have names like evil bird and good bird?

Ask them to point to the heaven door and pick that door.

On the other hand that's not really a question just a command. If you ask them "Can you can point to the heaven door?" you may just get a yes and no answer. It all depends on if the birds are being assholes or not.

Edit: Never mind that wouldn't work, fuck I'm tired.

Should I enter the door on the left?

Solution;
Clone yourself and ask yourself if you want to play a game, and that game is to each open a door at the exact same time. Whoever goes to Hell loses, and suffers eternal pain and punishment.

Whoever wins gets to stab the birds with a knife for being confusing cunts and then proceed chill out with Black Jesus and get plastered.

Too easy. Ask the left bird what the opposite bird would say if I asked it which door leads to heaven and go into the opposite door of what it says as if the left bird was the truthful bird it would tell me about the lie the right bird was going to say and if it was the liar it would be forced to lie about which door the truthful bird would say.