Mazdamundi starts the game with a single city - Hexoalt. This is one of the unique capitals of a province with 9 slots for buildings. Your initial enemy is the Skegg faction, which belongs to followers of Chaos of Norsca. To the North, there are ruined settlements but, watch out, there are Skaven there. To the South, there is an amiable faction of New World Colonies, but even farther Southwards, there are Greenskin Territories - Blue Vipers faction.
You will have to start the game by eliminating the Skegg faction, but your armies are quite weak now. Start by developing the main building in Hexoalt and start building there a Gold mine shaft - this will increase your income. Then, enter a trade agreement with New World Colonies. It is rather risky to attack the enemy right now. You have too few units and therefore, start enlistment of several units of Skink Cohort. Probably, after the turn ends, your enemy will attack you and you will have to crush his forces in the field. Although his forces will be sizeable, you should be able to do it. After you have gathered, around, 13 units, attack the Monolith of Fallen Gods and seize the settlements.
You can now destroy the Hatchery of Lower Castes in the province capital - the same building is in the settlement that you have just seized. Then, develop your forces and attack Ziggurat of Dawn. After you have seized it, issue an order to increase social order, development and income from buildings. In your city of Hexoalt, build Shrine of the Ancients (this will increase social order), Underground Lagoon (stronger infantry units) and Skink Gatherer Camp (this will speed up the province development). Now you will have to replenish your forces - here, it is a good thing to start replacing Skink units with Sauruses. Once you do that, set out to Skegg, which is the last settlement of the enemy faction. After you have seized it, retreat and set taxes in the settlement. You will now have to bring under control economy and contentment in your starting province, so Skegg will have to fare on its own, for now.
Now, spend several turns on development - in your settlements erect buildings that boost your income and development. Also, remember to develop Skegg as soon as this is possible, and erect the Shrine of the Ancients there. As soon as your economy becomes stable (around 1500-2000 of income per turn), and contentment in your starting province is sufficiently high, you can continue your conquest. Your next target should be the capital of the Viper Forest - Mirror Pool of Tepok. this area has been seized by Skavens, so watch out, they approach individual fragments of ruins - most probably, the settlement is occupied by Ratmen. It is also possible, that this area will be conquered by Dark Elves, in the meantime. Mirror Pool of Tepok is a ritual resource site, so it is highly important to seize it. Thanks to the site, you will receive a significant influx of ritual points (remember to erect an appropriate building there for that - in the case of Lizardmen, this is jest to Repository of the Ancients).
Later into the game, secure the Northern border - in settlements Fallen Gates and Ziggurat of Dawn, you should erect walls. Dark Elves from Ss'ildra Tor faction will surely declare war on you many times and will attack your territories. There is little point in conquering them at this point into the campaign - the harsh cold in their provinces disagrees with your faction. Apart from that, you will border more Dark Elves anyways, so you will gain little by conquering them. However two of their three settlements have trade resources (Wine in Ss’ildra Tor and Exotic Animals in Sulpharets) so if you want these resources you can conquer them. If you don’t want the resources, the best you can do is plunder the nearest enemy settlement and then destroy it. In this situation, all you can do is expand Southwards. Here, you will have to defeat a faction of Greenskins - Blue Vipers. The Lizardmen faction here - Xlanhuapec, will, most probably, also be hostile towards you. Your main goal in your conquest should be Tlaxtlan settlement, which is yet another ritual resource site. After that, you can conquer the rest of Lustria. When it comes to your relations with New World Colonies, it's up to you. Actually, this is the only friendly faction and you it may be advantageous to have a partner in commerce and an ally. On the other hand, you will not be able to unite the Settler Coast province because of its presence, as well as Pahualaxa Jungle. Therefore, both conquering them and entering alliance with them have their upsides.