2. Hopefully you don't have Flavored Start turned on, because it'll highly prefer Jungle, which on the face of things is okay but we'd have to waste our extremely valuable starting time either relocating or clearing Jungle so our city can grow. You need a couple good food resources (or grassland/floodplains near rivers), but beyond that prioritize commerce over production - you'll only need one tile within the 8 immediately adjacent tiles to give you at least 1 production. In fact, if you get a good set of flood plains/grasslands with food and commerce resources around but no forest or hills in sight beyond that one production, awesome - we'll be mostly producing workers and settlers anyway and it helps a cottage/sage/merchant economy.
3. Found your city ASAP - I give myself a single extra turn to get my settler on a hill so I can get early vision and spot nearby villages. Immediately have it build a Boss, and shift-click a second Boss as well so you don't forget. Between Barbarian and the cultural border, you're completely safe if you're playing against the AI, so explore around with both your Boss and warrior. While it seems underhanded since you're allied with the Barbs, explore any open lairs with the warrior as long as you don't have to go out of your way - you can't risk losing the boss to Crazed or something, but you can nab several nice rewards if you get lucky, including gold. Obviously it's much better if the boss nabs Villages, but it's more important to get as many villages as possible while those rewards are easy to obtain. I would give serious consideration to using my World Spell immediately after the Barbarians spawn; not only does this help me find enemy civilizations faster, the units have no upkeep (you'll lose them soon enough though) and they can nab villages for me as well! It's even possibly for you to get enough Barbarian units near a single civilization to end them right then and there. You can also save it for later - specifically for a potential awkward point where you're up against a heavily-reinforced Doviello and you either don't have Wolf Riders or you just don't have enough gold to crack them.
You need at least 100, preferably closer to 200 gold from village rewards before the animals come out in serious force. If you don't get this, either scrap the game or try a different strategy, but maybe 1 out of every 4 games I play has me with less than 100 gold by the time barbarians spawn. Also, there are only a few other potential results - recon units almost never get hostile villagers, so if you're not getting gold you're probably nabbing some free technologies that might give you enough science ramp to go the more traditional production route.
4. My research path goes as follows: Agriculture > Animal Husbandry > Education > [Crafting & Mining] > Calendar > Exploration > Festivals > Horseback Riding > Trade > Cartography (adopt City States) > [Crafting & Mining] > Bronze Working > Smelting > Iron Working. You should get Crafting and Mining after Education if you'd get enough commerce out of it, but you really really
really want to tech to Trade ASAP. If you have absolutely no Plantation-capable resources within reach, you're going to have to decide whether the +6 gold per city plus the Great Merchant(s) are more worthwhile than the early bombardment ability. Those are the
only technologies you need, and I highly suggest tanking your research rate in favor of gold and mass-producing Bosses once you’re finished with Iron Working, although some Champions for defense is never a bad idea.
AH gets you Wolf Riders, which are 4+1 poison with 3 movement for 30 gold - this is more than enough to take out Axemen pre-copper, and with a couple promotions or enough bonuses from being in the Boss's army, they'll take down Archers just fine. After Education, you should kick down your research rate and prioritize gold enough that you can hire enough wolf riders to take down your next target; the pillage gold should be enough to Enlist the ones that survive. Trade will get you Hill Giants for 70 gold, which start at 5/7 with 50% collateral damage (2 units) and the ability to Bombard for 20%; although the tooltip and Civilopedia entry don't mention it, they'll take Iron Weapons upgrades to get to 7/9 (maybe Mithril too, but you're Clan; if you get that late in the game you've probably lost already). Once again, after Trade, you might want to kick down your research rate even more, as Smelting and Iron Working give small returns compared to a much larger number of Hill Giants attacking your opponents.
Gold is far, far, far more important than Science with this strategy. Essentially, after Iron Working, you're either going to end the game or have only a couple opponents left to deal with. At that point, if you've been focusing on commerce, your bosses will be able to mobilize a far larger force in a short period of time than you could possibly dream of producing otherwise, so even though you could field 8-strength Champions, you'll probably end up sticking with Hill Giants.
5. At this point, your second boss should have finished and begun exploring. If you're in a central area and have yet to find an enemy civilization, have them explore separate directions, otherwise rush the second boss up to the first and stack them. Depending on difficulty, you may have to stack your bosses regardless because of the increased number of warriors defending early on higher difficulties. Just remember - and this is
extremely important - be super cautious if animals like Cave Bears hit the board. You cannot afford to lose a Boss at any point in the early game, but this is probably the worst time for it to happen. You should pretty quickly run into an enemy civilization (well before they could possibly research Archery), and your boss(es) should be sitting outside the borders. If that civilization is very strong early, such as Doviello, they'll be favorably disposed towards you anyway so I might suggest skipping them, but very few civs will be strong enough to stop you this early. Now it's time to have some fun.
6. Be very liberal with your summons. They are there to be sacrificed so your high-experience Enlisted troops can finish the enemies off. You can sit outside the enemy base (assuming no catapults, otherwise have a couple units ahead to soak up that damage) and spend 2-3 turns summoning to crack a really tough one. It works extremely well. Generally you should only Enlist when it makes sense, because 50 gold is almost 2 Wolf Riders; you want several high-experience Wolf Riders, but there’s no reason to enlist every troop that survives. Remember that you can summon 3 warriors for the price of a Wolf Rider, and if you're facing enough low-power enemy troops, it might make more sense to just summon warriors earlier and hit critical mass, and then just summon wolf riders when you reach the base to deal with Archers.
7. Easiest-case scenario is somewhat distasteful - you manage to finish Animal Husbandry before your boss(es) reach the first civilization. You should still find them well before they could have possibly researched Archery, so summon a couple wolf riders and a warrior, add them to the Boss and slaughter the defenders (if they have a
lot of warriors use straight-up warriors, though). Enlist any high-experience Wolf Riders – they’re way too useful to just let them go Barbarian, and at 30 gold a pop, it ends up being more worthwhile to keep the better ones.
If you have only one boss at the target civilization and it’s before AH, then hire a warrior, have it join the boss's army, then declare war and move one tile towards the city. Repeat this twice more, and you'll be sitting outside the enemy city with 3 warriors attached to your Boss. Summon a 4th warrior and send the three you just summoned into battle, attaching the 4th and following up with him and then your Boss (use Waaagh!) if you need to. You should be able to destroy the civilization if it's early enough - if you need more than 6 warriors, you'll need a second Boss because the chances that one of your warriors goes barb is way too high at that point; even 5 warriors can be hard to gain and keep with a single boss.
If you have two bosses, step into the enemy's borders before you summon, which will give you up to 6 warriors attached to 2 bosses - if you need 8 warriors for whatever reason, you can start outside the borders, but there's a decent chance that one of them's gonna go rogue. 2 bosses should be enough to eliminate almost any civ in the game if you come at them early enough.
After you take over, if the city's too far or
for commerce just raze it. Otherwise, leave all your warriors at the city, and have it produce a warrior first thing. It's not worth the 50 gold to have even a high-experience warrior just sitting in that city, and you should be able to get that new warrior up before or soon after the remaining warriors go rogue. If your bosses were the only ones left, you’ll want to at least wait until the resistance period is over, but you should be okay leaving the city undefended for a bit. After the warrior is produced and fortified, produce a boss, then a Monument and continue as you would any normal city. The bosses should prioritize the increase-minion strength promotions before anything else.
7. After you get AH, make sure you always run a gold surplus, and consider making it a decently hefty one (one set of wolf summons for 3 bosses is 90 gold, but you'll more than likely need gold for two sets plus another 50 gold for enlisting the ones that survive). After your third boss finishes, pump out a warrior for defense (finally), then a couple workers, another warrior (for escort) and a settler. Then focus on workers and settlers (and escorts!) as needed - you want to spread as much as possible to maximize happy and commerce resources to get your cottage economy working well which ends up producing even more commerce. Favor locations with enough food to let you run specialists and cottages. If you tech to Festivals, be sure to assign a Merchant in every city after you build the Market. You may be able to bulb Trade with the Great Merchant, but off the top of my head I don't recall whether another researchable technology will prevent that from happening. In any case, you can always settle him for 6 more gold a turn, which is huge combined with the +6 gold/city you're already getting.
8. During that expansionary period, your 3-4 bosses will hopefully have eliminated a couple more rival civilizations with the ridiculously-powerful Wolf Riders (for that point in the game anyway; a summon-able 5-attack, 3-move unit with no city attack penalties by turn 30 or so is just ridiculous). Don’t summon more units than you need to, and try to summon them as late as possible. Be sure to continue to Enlist high-experience Wolf Riders, because they quickly become your bread-and-butter unit. Add a boss for each Civ you defeat; you may not need them now, but they'll probably come in handy eventually. Continue to expand at a rapid pace – being at peace with the Barbarians gives you a ridiculous advantage compared to other civs, and you need to ruthlessly exploit it. Hill Giants are
expensive, and you’ll probably favor Wolf Riders for a long time besides the odd couple Giants to soften up stacks, but you’ll need more and more gold as time goes on. It’s imperative that you focus solely on expansion for commerce and slaughtering every civ you encounter, because the later the game goes, the smaller your edge gets, although if you have enough Bosses and gold you can make up for almost any deficiency.
9. Eventually you’ll hit Trade and be able to summon and enlist Hill Giants. With your army of workers, you should have no problem making sure you have a decent road network to the front lines so you can get Bronze Weapons to them once you get a chance. Hill Giants are your sacrificial shock troops – you summon 3-5, bombard the city, then next turn send them in first to get the enemy stacks to the point where your experienced troops can mop up. You may not want to Enlist them right away, besides one for defense on eac h town you take, because they’ll slow your army down and 5 power is plenty at this point in the game with the collateral damage if you summon enough of them.
10. Have fun managing a conquer victory well before any civilization gets to Champions! It can get a little formulaic after awhile, and it becomes really obvious when you have too much momentum to lose, but the sheer power of having 6 bosses drop 18 Wolf Riders on some poor city is exhilarating.