My method of fighting:
This method was developed after a short time dealing with the beasts in the abyss and is pretty effective. Normally you will get out unharmed and very happy
(Note: This supposes you use melee weapons and it is not very effective against monsters using strong missile weapons/spells)
1. Spot the enemy. When it's more than one, concentrate on one, don't be brave, or foolish.
2. Keep your distance, then load you attack. When the power gem is bright green, rush towards the enemy and attack.
3. Don't stay near him! You can either continue running to escape his attacks or walk backwards being out of range of his weapon. You can turn and run too.
4. Spot the enemy again and prepare your strike. Charge against him and strike, then avoid his attacks. Repeat this until it is dead.
It takes some time to master but you can kill the fiercest monster easily (it may take some time, this is the most irritating factor that unfocus you). The gargoyle in the top of the screen shows your opponent's life. Bright green is good health, yellow means it is hurt and red means seriously injured.
You can say this is 'Hit and Run' but I prefer to call it 'Fight for life'.