Dungeon Keeper level 10: Nevergrim.

Difficulty: Depends on who you transferred in from last level. Easy if you cheat, but who wants to play fair?

Your Portal max: 25 creatures.
Enemy Portal max: 20 creatures.

Starting forces: 4 Imps (1st level).
Enemy's starting forces: 5 Imps (1st level). Also has a massive Lair for free.

Starting gold: 6000
Enemy's starting gold: 16000

Possible minions:
Attracted through portal: Dragon, Warlock, Orc, Bile Demon, Dark Mistress, Hellhound.
Found elsewhere in the level: Fly (4x 2nd level), Dragon (4x 1st level).

Rooms:
Known at start: Basic Five.
Can be researched: Bridge, Guard Post, Workshop, Prison, Torture Chamber, Barracks, Temple, Graveyard.
Can be found elsewhere: Scavenger Room.

Spells:
Can research: Sight of Evil, Speed Creature, Call to Arms, Conceal Creature, Cave-In, Heal, Lightning, Protect Creature, Chicken, Disease.

Doors/Traps: Wooden, Braced, Iron, Magic Doors; Gas, Lightning, Lava, Boulder Traps.

Enemies: One enemy Keeper.

     Take a look outside your Heart. Prepare for a shock. See what I mean? No walls...

     You can win this realm very quickly if you've transferred Horny in. Simply Possess him, run him straight over the lava to the enemy realm, and smash the enemy Heart to bits. There's nothing he can do about it, none of his creatures can hurt Horny badly...

     Otherwise you'll just have to do it the hard way. The lack of walls means you won't be putting doors anywhere except around your Heart, and you can't rely on any creature walking into a trap with no corridors to channel them down. So, no need yet to build a Workshop. Nor can you attract Trolls in any case, even if you wanted to: you're lucky in this realm, in that nearly all the minions you can attract are useful.

     You want to start by claiming territory reasonably fast, so spawn maybe one or two more imps. They will find a Scavenger Room. This will allow you to attract Hellhounds - not that you really want to, they're not great. In fact, as scavenging costs money which you haven't got (with no access to gems), you're best to sell the room immediately. If you've transferred a Vampire, Warlock or Dragon, get him researching immediately.

     In a realm where you are attracting Dragons directly, you need all the lair space you can get: dragons take up no less than 4 lair tiles. You want a large Lair, Hatchery and at least 25 tiles of Treasure Room - although, with a lot of gold spread out, you want it in several different places near the gold, rather than one large 5x5 room. Build your Lair adjoining the lava, so that your dragons can gain experience while sleeping (although this experience is pretty minimal.) Library behind the Heart, training room in front. Get ALL your creatures training. Don't bother building a Prison or Workshop, or indeed a Graveyard or even a Temple (or any more Scavenger Room tiles), they won't be of much use to you in this realm.

     You want to get Bridges as fast as possible, then bridge forward to the central gold island immediately. Dig straight through to the centre, in a straight line, and release four Flies to join you. Let them explore the entire realm, then bridge around and directly over to the large land areas on the side to get the two Increase Levels. It doesn't matter if the Flies get killed running into the enemy island - you can, of course, Possess one to explore more efficiently. You may run into up to four unaligned Dragons wandering around the lava, minus any that have already been claimed by you or the enemy. Dig out the central gold island BEFORE you go for any more of the gold on your own island than you have to. If the enemy bridges to the central gold island (or, worse still, to your own island), then bridge up to his bridge, then claim and sell his bridge.

     Eventually, the enemy is bound to run out of gold, while you still have some available. At this point, train your creatures a bit higher, use both your Increase Levels, and attack in force. You outnumber him, and are of higher level, so you should beat him easily. He guards a Transfer Creature, which you will find whether you won the sneaky way by transferring Horny or the hard way by simply outlasting him in the gold stakes: use it on a high-level minion, as usual.

     (Hint in advance: The best minion to transfer, in this case, is either an Orc or a Mistress. Dragons are normally great, but one weakness they have is that they don't win fights very fast unless you are Possessing them and can apply the flame breath correctly: the AI is less good at flaming things, and next realm is not one for the possession mode.)

     (MAJOR hint, especially useful in future levels, Deeper Dungeons levels, and many custom-made levels:
     There is a way to make money from your Workshop, if you are short of gold: place and sell doors, and get creatures to make them. This works especially well with Magic doors, if you can force your workshop to build only these - which you can only do by having at least 2 or 3 of each *other* type of door and trap present in your workshop, but don't place them, place only the Magic Doors as and when they are made.
     In this case, you can use this feature to get enough gold to train the creature which you wish to transfer all the way up to level 10 - throw back into the portal all high-maintenance creatures that are not good at manufacturing, such as Dragons, Vampires and Mistresses, and staff your workshop with Skeletons, Orcs, Trolls and Bile Demons, and make magic doors while *one* creature, and only one, trains up to the max, after you've finished the level: you don't really need to do this, but it can be fun when you get him there. Or boring, going through the chores of actually *getting* him to advance. Your choice...)