Reason is the basis for knowledge

Reason is the basis for knowledge and therefore the way to determine what is true.

For example, under empiricism [the philosophical view that knowledge comes from sensory experience and observation] they will use reason to formulate a hypothesis, construct an experiment, and evaluate the result. So, an empiricist will, in fact must, appeal to logic/reason to obtain knowledge. And this is true for any other schools of thought – everyone will appeal to reason to defend their view as well as criticize/evaluate other views

Reason or Critical thinking is the act or practice of careful goal-directed thinking (i.e applying reason and questioning assumptions) to solve problems, evaluate information, discern biases, etc. The 
Stanford Encyclopedia of Philosophy states: One could sum up the core concept that involves these three features by saying that critical thinking is careful goal-directed thinking. We use Critical thinking for analyzing and/or evaluating information gathered from various sources as a guide to convictions and action in everyday life and in all fields of inquiry. 

A Christian may say that revelation is knowledge, but they must still reason from the Scriptures, as in Acts 17:2,17

Note: if one uses reason to criticize my claim, that's actually validating it - you are using reason to gain knowledge as to the validity of my claim.

Objection 1: Rationalism begs the question - the rationalist will use a rational argument as a premise for the conclusion of his argument.

Reply: To this, I say no, it is testing a hypothesis. Test all epistemic theories, see that all use reason.

Objection 2: I can use reason to gain knowledge about the Lord of the Rings. I can gain knowledge about a fictional universe, but that doesn't make it magically true for our reality

Reply: If one is gaining knowledge about the LOTR, then they should be able to gain the information that it's fictional.

Objection 3: One must use evidence along with reason to conclude they’ve learned something about reality and not about something in their (or someone else’s) imagination. Otherwise, there is no way to differentiate between knowledge about reality and knowledge about fictional universes.

Reply: First, notice that you did not use evidence in this, so you seem to have refuted your own point. Secondly, you cite "reality"; what is it, and how do you know?

Objection 4: Your appeal to “reasoning” as absolute authority is circular. You assert that “reasoning” is the ultimate authority because that is the only reasonable means for ascertaining truth.

Reply: Circular reasoning is when the proposition is supported by the premises, which are supported by the proposition, creating a circle in reasoning where no useful information is being shared.

But my argument stems from the fact I investigated other schools of thought until it dawned on me that everyone uses logic or reasoning to make their case, including empiricists, skeptics, intuitionists, etc.

Note: These pushbacks come from previous conversations about this topic.

To sum up,

1) reason alone can be used alone to gain knowledge 

 

2) every other method must employ reason to gain knowledge, otherwise their preferred epistemological model doesn't work

 
3) All criticisms of my view will invariably use reason to validate their analysis.

Other posts you may be interested in:

Skepticism is Not Critical Thinking

The Inference to the Best Explanation

The Consensus of the Experts Say... 

Atheism is a non-reasoned position/view

The Three Laws of Logic

Justified True Belief

Philosophical Naturalism is logically self-refuting