Easy and realtively fast way to level up combat skills without cheese involved. SOLO CHARACTER

So this guide explains what it says in the title, let's get started;
(by the way, this is assuming you pick some start located in the hub or nearly by)

1-As soon as you've spawned, get the free loot in the abandoned shack that it's in the hub and sell it for profit. Then, head towards Admag and visit the ruins that are midway. There you should find a guaranteed high quality rusty chainmail, equip it. Take all the rest and sell it to Admag. You can also sell the materials located in the ruined holy outpost and the tiny settlement that you can find in the eastern Border Zone territories. Take all the money and go to Squin or Admag, use it to buy some armour. I would recommend the samurai one, standard quality at least. If you can, get also some head and leg protection. THIS SHOULD TAKE 2 IN GAME DAYS AT MAX

2-Get the worst weapon you find (that's not necessary if you want to go martial artist). Now go out there and find some hungry bandits. Fight them in block mode. If you have good enough protective gear, you should be able to get up after the beating, avoid getting more than -10 health in any vital points or else you're already dead (that's what the gear is supposed to avoid). When your character is playing dead, wait for the bandits to start leaving and force him/her to get up. This should boost yout thougness incredibly fast. Repeat the process until you get like 40 thougness, or a knock out limit of like -40. Don't stop until you get there, that's important to make sure you won't die in future beatings. THIS SHOULD TAKE AROUND 3 TO 4 IN GAME DAYS

3-Now it comes the funny part: build an outpost near Admag. A shack will do, you can also get a sleeping bag and place it inside the building to rest and recover. Now all you have to do is to wait: you should get the shek kingdom tax raides, as well as the dust bandits, band of bones and kral's choosen raids. The sheks will send you the Tribute Round. Refuse all of their demands and you will get the Return for blood raid in about a day. Set your character in block mode and defend yourself. They will send warriors with stats arround 40 and a shek scout with stats arround 50. This will boost your defence skill very fast. Keep taking the beatings until you get arround 40-50 in defence. After that, set your character in attack mode and start training your attack against the raids. THIS WILL PROBABLY TAKE ABOUT ONE IN GAME WEEK

4-The best part of this training method is that it's completely safe if you have first leveled the thougness, and doesn't require you to look for the enemies since they come at your door. Now, your solo character should have attack and defense arround 50. Eventually, you should be able to defeat the Return for blood raid, which will activate the Shek Challengers raid. This will send you a big raid of about same stats enemies (40-50). Once you manage to defeat it, you will get the Shek Revenge raid, which will consist of warriors with stats arround the 60, so now you will have again some fast stats gains. THIS WILL PROBABLY TAKE ABOUT ONE IN GAME WEEK

5-So by day 20 you should have a decent fighter with combat stats arround the 60-70, and if you have sticked to the same weapon type you will be able to deal some damage. Now, take out the Border Zone's bounties (Dust king, Dimak and Buzan), which will guarantee you arround 75k cats. Use the money to get some really good gear and a decent weapon (you can visit the armour king and/or the Black Desert City), and you will be ready to venture out to the world and start kicking ass real good. You still won't be a god, so don't try taking the Heng on your one, but you will for sure be able to survive almost any map zone and to capture most of the bounties, except maybe for the biggest ones. And without chesse involved, of course.