When atheists and Christians argue, who uses more logical fallacies?

It is so close that no one can call it! Both sides are like a dog chasing it's own tail.
The simple fact is there are not universal tool to use to decide who is dealing with facts and who is dealing in what amounts to legend or myth.
I am by the way a Christian and have friends who are atheist. We have some very worth while discussions because we are educated enough to realize the foundations of both are based on subjective interpretation of objective evidence.

Christians of course.  Atheists have logic and reason on their side and need no bullshittery

Atheists don't have any arguments at all. Non-existence, of anything, cam never be proven. Proof requires evidence, and a non-existent entity cannot provide evidence of its non-existence.

Gods and Goddesses are rumoured to be undetectable, and yet, are ALSO rumoured to be able to influence events in the material world.

So, why DEBATE?

Why not simply produce something which is testable, repeatable, consistent, and cannot be ascribed to random chance?

Toss a dozen coins into the air, notice that they land in random array, face up or face down.
Recite a brief prayer, toss the same coins, and they all land face UP, every time the prayer is said.
No matter who tosses the coins, or which coins, or who says the prayer.

A God or Goddess which is not stronger than random chance, is scarcely worthy of worship.

Atheists don't make arguments because they are only claiming we are at the default of nonexistence because theists have not met their burden to produce an argument that works. Atheists point out the flaws in reasoning that theists make in their determination that any Gods exist. Nonexistence leaves nothing, and that is what atheists are claiming we have "nothing" to even hint at a "real" possibility of magical, nature defying, super Beings.

Some theists want to argue that the absence of evidence is not evidence of absence, but it certainly is unless you have something to shed light that it may be possible. For example, life on this planet grants the possibility of other life in our universe even though we have no evidence for other life. There is nothing that grants the possibility of Gods and actually things that demonstrate the concept, like a square circle, is in fact impossible.

Only agnostics and theists have the burden of proof. Agnostics for the "possibility", like I did with my other life example, and theists for the actual existence. Atheists are not making a claim, they are rejecting two claims, one for the possibility and one for the actual existence.

Remaining at the default of nonexistence is not a claim, it's the starting point. It requires "something" to move to agnosticism that supports the possibility. It requires "something" to support actual existence to move to theism. Atheists require "nothing" because the default of nonexistence requires "nothing".

As a final note, logic only gives you "logical" answers based on the premises injected, not necessarily "reasonable" conclusions. The premises must be reasonable if you also expect the logical conclusion to also be reasonable. I have seen some theists inject unreasonable premises and performed perfect logic to the logical, but unreasonable conclusion. Logic is like a calculator, you can input the wrong numbers, but you will still get an answer.

I don't keep tally.  I just tend to point it where ever I see it.

They do.

My arguments are perfect.

Christers every time do kid... theirs nothing logical attached to religious belief ya see whatsoever

Religious believers use more logical fallacies, since they live in a fantasy world and fairy tales.

Christians. They disregard science and logic completely, thinking a stupid book holds all the answers.