Realm of asuras
Asura is a Sanskrit word that means "ugly." Male asuras are extremely ugly; the females are beautiful. It is the nature of the male asura to initiate fights. The female asura is also naturally fond of fighting, but wages covert wars, unlike the overt physical battles of the males, using weapons of the mind such as jealousy, obstructiveness, ignorance, and affliction.
Sometimes this realm is included in the Three Good Realms— gods, humans, and asuras. At other times they are classified as one of the Four Evil Realms—hell-beings, hungry ghosts, animals, and asuras.
There are asuras in the animal realm, in the human realm, in the heavens, and among the hungry ghosts. Although the asuras are an individual Dharma Realm by themselves, they appear in the otherrealms as well. In general, regardless of what realm they are in, they like to pick fights, and they have bad tempers. They enjoy bossing others around and like to be supervisors, but they can't stand supervision. They won't be controlled by others. These are the characteristics of asuras.
If you haven't noticed the asuras, I can tell you more about them. Among people, asuras can be good or bad. The good asuras include military officials and troops, and bad asuras are bandits, thieves, robbers, thugs, murderers, and the like. We can see these asuras in the world of men.
There are also asuras in the heavens. Heavenly asuras wage battles against the heavenly troops of Shakra. From morning to night, they attempt to overthrow Shakra so that they can seize his jeweled throne and become the heavenly king. But no matter what strategy they use, they are always defeated, because they are "laden with blessings, lacking power." They have accumulated the blessings that earn them rebirth in the heavens, but they have no authority there. For that reason, they are invariably defeated in their battles with the heavenly troops.
Are there asuras in the animal realm? Yes. Tigers, for instance, are asuras among the animals. Lions and wolves are also asuras among the animals. These asuras bully the other animals. Wolves, tigers, and lions kill other animals for food. They prey on other animals because they have the nature of asuras. Snakes and eagles are also asuras.
In general, asuras are utterly unreasonable and have huge tempers. They are constantly blowing their tops. Too much temper!
There are also asuras in the hungry ghost realm, and they go around bullying other ghosts. The realm of hungry ghosts has kind ghosts and evil ghosts. Evil ghosts are utterly unreasonable. Ghosts are not reasonable to begin with, but these asura ghosts are even more unreasonable. And so the verse says: Asuras have a violent nature. They have explosive tempers.
Laden with blessings, lacking power. They have heavenly blessings, but lack heavenly authority. They fight for power and advantages, but fail to obtain them. Absolutely determined to fight: they love to fight and wage war. The modern world is a world of asuras—everyone is fighting and struggling, trying to knock each other down.
Asuras are so belligerent that they can keep fighting for one hundred, two hundred, three hundred, five hundred, or even a thousand years. They could fight for a thousand years without getting tired of it!
This is the Age Strong in Fighting and also the Dharma-Ending Age. Nevertheless, we don't want it to be the Dharma-Ending Age; we want the Proper Dharma to prevail. We should vow that wherever we go, the Proper Dharma will prevail. If we do that, every place we go will become a place of genuine Dharma. If everyone fulfilled this vow, the Dharma-Ending Age would become the Proper Dharma Age. We can turn the situation around.
They bob along in karma's tow. Asuras may be born in the heavens, in the human realm, or in the realms of animals and hungry ghosts. Dragged by the force of their karma, they become deluded, create more karma, and undergo the retribution. The force of their karma pulls them to undergo retribution in various realms. Cultivators should take care not to be belligerent and hot-tempered. Then they won't get dragged into the asura realm.
Five of the nine Dharma Realms have asuras. In the animal realm, there are asuras among creatures that fly in the air, those on the land, and those in the water. Crocodiles are an instance of asuras in the water. Wild stallions are asuras among horses. They bring trouble and disturbance to the herd. Most bulls are asuras, too. They butt their two horns against things to show their tough asura disposition. Bulls are asuras by nature. Dogs have even more of an asura nature, so people who own dogs are in close association with asuras. If you hang around asuras, you become closer to them. And getting close to them is dangerous; you might just fall into the realm of asuras. Everyone should pay attention to this and not run into the realm of asuras!
This is the realm of the Asuras, the jealous gods or titans. These are powerful demigods who are perpetually at war with the gods of the lowest heavens. These are beings devoted to warfare and everything that goes with it; anger, pride, lust for conquest and so forth. Beings in the human realm who manifest these qualities are experiencing Asura-consciousness and are laying the foundation for rebirth here.
There is a Jataka which describes the origin of the war between the gods and the Asuras. (no.31) At one time, it seems, they shared the same realm as the gods of the first heaven. This is located at the summit of the mythological Mt. Sumeru, the world-axis. On the slopes of this mountain there grows a huge tree with intoxicating fruit. The Asuras, being coarser than the devas, were more heavily affected by the fruit and lay about in a drunken stupor.
Sakka, the king of the gods, decided to be rid of these loutish fellows and had them grasped by the heels and tossed down the side of the mountain, to the roots of the tree. Coming to their senses, they realized what they had lost and have been fighting to regain their lost place in heaven ever since.
Generally they get the worst of the battles, because the gods are very hard to kill - they recover quickly from any wound and the only way to finish them off in war is to sever the head. It is indicated in Digha Nikaya 18 that at times when righteousness prevails amongst humans then many more are born into the realms of the devas and the Asura host declines. If this is so, then perhaps the are doing better these days!