How can I make my NPC or character blink on being hit?

Questions & Answers
1

I am using Unity to make a 2d game. My NPC is modeled using Maya, and I am using a very simple shader Unlit/transparent on the materials. Now, I want to make my NPC brighten up with some red color but I am not quite sure how to do this, especially how to make the character brighten up.

2

You need an emissive color. Diffuse get multiplied by the light result, emissive is added.

A simple way to have it blink then, is to multiply the emissive color by a Mathf.PingPong( Time.time * speed, 1f) inside a coroutine.