It's easy enough to get 100% in Destruction, and easier to get 100% of Domination.
If you want to be the good hero, then you should just do all the tasks in a good way, but it can be difficult to do nordberg and elf line to your slaves as you can easily get lost.
But the evil was Ossetians little silly, I must admit, I tried to implement the game 3-5 times before I found out how to get it to 100%.
The secret is before you go to the last boss, so you can take a Empire sewers that you just kill the people there are and you need Ossetians destroy the houses, because there are people inside them, then when you are done, you can teleport to another place, and when you come back to Empire sewers, then people know there again, and so you just know so that you've got 100%.
1. Brown minions are good in fighting, but die quite fast. If you have already conquered the first area Nordberg then you can head to the anvils where they make armor, but im sure it only works if you conquer it, not destroy. Also, kill enemies and they might drop gear for your brown minions.
2. Avoid making the Overlord fight to much, though he seems quite powerful, he is weak by himself in battle so always look for ways to gain more minions.
3. Before you take on other areas and eventually the last boss himself, try to benefit from the areas you have conquered, take the minion orbs and look for special objects you didn't notice the first time you played through it.
4. If you unlocked all minion types it is wise to have a fair amount of each minion type, the best order is atleast 20-25 brown minions, 10-15 red minions, 5-10 green minions, and definetly atleast 5 blue minions to revive your dead minions.
5. If you are the type to gain trophies, then try gaining some from your mistresses, if you have enough gold, buy the full set for each to please them and unlock there special cutscenes, and finally split the tower objects for each mistress seperate with the overlord banner to gain the mixed cutscene and recieve the last trophy from the mistresses.
6. Search for special objects and avoid a large loss of minions, if you lose most out of all of your minions visit conquered areas and gain minion orbs to spawn more minions.
7. When you have enough of the items, head to the Forge and gain the best armor, spend no time getting other armor sets, because the objects needed to make them are fairly rare to get in the game.
If you want to get all your minions over the water, first leave them behind and head over the water yourself, then place a marker for them to stay on in front of you, but not too close to the water. If they don't run through the water, don't worry!!! Repeat the process until they all go through and hey presto! You can access areas easily with all types of minion!