What is the best martial arts in the wold?

Answer 1

Fundamentally you need the capacity to enter into position to apply your system's methods, and the methods need to be dominant from that position. That's a mild restatement of force the opponent to fight "your fight", and be better at "your fight" than your opponent is. The discussion below starts with empty hand since that tends to be what people think when the term Martial Arts is used.

Muay Thai is an example of an excellent art. It has very powerful fast long range kicks that are very difficult to close against. If you cannot bridge the distance against a good Thai boxer (not an easy thing) then you can expect to take quite a bruising.

Another example is modern free style Wrestling when combined with an effective ground submission system (sambo, bjj, "ground and pound", submission wrestling, etc…). Freestyle wrestling provides a strong capacity to bridge the gap in the form of its shoots, and it has a range of extremely effective takedowns.

Another excellent art is Yiquan. It has excellent lateral mobility and strong standing strikes and throws. The extremely fast lateral footwork gives the Yiquan practitioner a good chance to bring the fight to stand up fist fighting range, and their powerful hand methods often allow them to dominate once their favored range is established.

For "short" bladed and impact weapons I would recommend an established military system like Pekiti Tirsia Kali or perhaps the Systema that is associated with Mikhail Ryabko.

For long weapons, the Northern Chinese Liu He spear, Miao dao 2nd form, Feng Mo Gun, and whip staff are all first rate.