Arnis, also known as Eskrima and Kali, is a real-life fighting style that is used in the Tekken universe. It is the national sport and martial art of the Philippines. The three names for the art are roughly interchangable umbrella terms for the traditional martial arts of the Philippines ("Filipino Martial Arts," or FMA) that emphasize weapon-based fighting with sticks, knives, bladed weapons and various improvised weapons.
Eskrima is a style of combat that emphasizes on weapon-based combat that generally involves sticks and knives. An unarmed variant of the style focuses much more on reacting to and countering an attack rather than offensive striking. However, viscious strikes and kicks are still used.
It was first practiced by Filipino natives, and originally, it was an attacking style akin to assassination, especially when weapons are involved. However, the martial art was driven underground during Spanish occupation, but survived by being disguised as stage play. Eskrima became involved in the history of the Philippines due to its utilization during colonization and the world wars. It is said several Eskrima grandmasters were war veterans, who continue to develop the art and teach newer generations even today. There was initial resistance on teaching Eskrima to non-Filipinos, but was eventually allowed, contributing growth and renown to the style.
Eskrima today is used not just by Filipinos, but law enforcement agencies, security details, and is even infused to other martial arts. The Armed forces of the Philippines uses a special branch of Eskrima/Arnis specifically for combat called Pekiti Tirsia Kali, which is also taught to other soldiers, even to those from other countries. Eskrima in general features simplicity behind its concept and practicality, with blindingly-fast striking speed, based on natural human movements.