With the elfs good to mirkwood and make archers, spearmen and swordsmen. With the spearmen have them do a porchpine stance in a group of trees were calvary always go through. With the archers put them scattered through you're base by trees and with the swordsmen put them at the enterances on trees after a while send them all to the enemy base with calvery and blow the place down

Ok make a hero you would like to train and once he/she is made take them outside a creatures lair and put them on defend mode and place them close enogh to the lair that the monsters will attack them but not close enogh that they will attack the lair. And while the monsters keep attacking them they will keep killing them and grow lvls

On a skirmish when you are urikhi build alot of beserkers and train them on the native creatures until they are like lvl five and then have them defending your base and when enemys come near kill them with the beserkers becouse they are like as strong as heros when trained