This is a scripted level that introduces the game. You must build a 9 tile treasure room, mine 9000 gold and build a 9 tile lair to unlock the hatchery (in fact it will force a beetle through your portal and then give you the hatchery). With a 9 tile hatchery you are given the power imp spell but most important you have "unlocked" the heroes. Once you reach 7 creatures, the first wave of heroes appear (2 tunnellers), after you kill them you must wait 25 sec (and still have 7 creatures) for the final wave (1 knight a.k.a. the lord of the land). You win when all heroes are killed.
The strategy here is to possess the portal as fast as possible (asap). Creatures comes from portals at a given rate, the rate here is 1 creature every 20 seconds, so I've to take the portal before 20 sec or wait another 20 seconds :s. I then build all required rooms and hope I'll get 5 beetles for the knight. Flies are the worst creatures, beetles are not good either but they punch much harder. Incompressible time is 7x20 + 25 = 165 (2:45). Improvements can only be made during the fights; 3:03 is possible but very hard.
0:13 look at those lazy imps not going at work. Imps are very very very ... stupid, I hate them and you will see me slap them again and again :p 0:20 the first creature is coming and requires a lair. If I don't build the lair, no more minions will come serve me. 0:41 second creature is a beetle, try to do the same :p 1:50 I made a beetle effigy to attract them, no one as yet proven it works ;) 2:40 I give chickens to my beetles so they recover some health (they absolutely didn't need it this time, I agree) 2:54 perfect knight fight with 5 slapped beetles at the right spot