I will reveal my grand strategy! Which is probably dumb because I’m sure my strategy will get nerfed/killed but I want to make the game as fun as possible for as many people as possible 
My Strategy
I really like the celestial pools map, I choose elves in the map. Within 6 leagues of either elf starting settlement is a goblin settlement. In my deck I put:
- Elf: 16 elder mages
- Elf: 20 high elf mages
- Goblin: 13 dealers (I’d put more but that’s all I have for now)
- Goblin: 6 goblin royalty
Starting Out
I deploy whatever elves I can (usually mages) and grab whatever’s within 3 leagues of me with my mages. I activate whatever elder mages I have immediately to make sure my mana is increasing steadily. I deploy elves in the following priority: elder mages, dark forest witch (comes as starting units, cheapest mage unit), high elf mage or the tree whisperer. I use my starting elf archers to go down (or up) to the closest goblin settlement as quick as possible.
Getting my First Goblin Settlement
At this point I’ve used the elder mages probably twice and am around 40 mana or so.
I deploy any goblin dealers I have as soon as possible. I also deploy any goblin royalty cards if I don’t have any goblin dealers in my hand. I’ll convert 10 valor for 200 gold if I run out of money. Hopefully I have at least one goblin royalty and some dealers deployed. If I have a goblin royalty with me I activate it to get more gold and deploy more goblin cards. If I ever run out of goblin cards in my hand (just have elf cards) I deploy elves in the following priority: elder mages, dark forest witch (comes as starting units, cheapest mage unit), high elf mage or the tree whisperer.
I try to grab any goblin settlements around me. Any gold I get I put into dropping more cards, with my preferences towards goblin cards.
I spread out at least 1 high elf mage (usually 2 or 3) far into each corner of the map. I keep most close to the elder mages to keep pumping out mana.
End Result
What happens pretty quickly: my mage cards will cost very little and at a certain point they cost basically nothing or I actually gain money by deploying them. I empty out my whole hand and have the elder mages producing about 1,200 mana every 12 turns. My high elf mages can kill anything from a 6 league range so start killing huge masses of zombies (2k or more) and any zombie lords. Any gold I gain isn’t important at this point so I distribute gold, valor and mana to all the other players so they are all pretty hugely pumped up. It’s basically clean up at this point since the zombies can’t cope.
Things I Watch Out For
Zombie lich: they don’t show up as much, usually the zombie lords in celestial pools are jesters or masters of coin. Any zombie lich I immediately target as it can seriously hamper me. The spread out high elf mages take of these.
Zombie jesters: honestly these aren’t really that big a problem but the people I’m playing with start to freak out as they get to be strength 10,000 or more. I just get enough mana to eventually kill them in one shot with a high elf mage.
One Interesting Side Note
If one of my allies deploys a goblin spider pennon I don’t need a goblin settlement to deploy goblin cards. I can just deploy to the spider pennon.
Suggested Gameplay Changes to Balance/Nerf this Strategy
Nerf Strategy 1 (what I would strongly recommend)
From a player perspective it’s better if you don’t mess with strategy at all from a card side. This is simply for customer service: players who find out optimal ways will feel punished if their strategy doesn’t work anymore because you changed the cards. They’ll feel like they wasted time/money on getting certain cards that if nerfed they suddenly feel like it sucks. I would instead suggest changing the zombie lords to make them more deadly and adapt to this strategy.
Change the lich king, master of coin and the valor stealing zombie (don’t know the name) to steal only half of all of that resource. Also make them only killable in melee combat (give them the forge flesh ability of the ironhide zombie lord). For every X amount of mana, gold or valor stolen create a new zombie unit: chaos elemental (for lich), gold golem (for master of coin) and onyx ravager (for valor). These units don’t use any bodies and just spawn wherever the zombie lord is. Now this strategy will increase the danger for everyone and people will have to compensate. Making the zombie lords invincible except in combat means the high elf mages can’t target them.
Alternate Suggestion
Instead of giving zombie lords forge flesh give them mana absorption: mage abilities increase their power instead of killing them. That way things like dragons can still kill them but the strategy of mages can’t (and stops the other potential strategy of goblin charming rogue/little wizard which is basically the exact same strategy as above).
Additional Possible Nerf
Make high elf mages/eldermages speed 6 or 8 hours travel by road. Flavor is they are old and slow. This just makes it harder for them to react and get to places they are needed
Additional Possible Nerf
Make goblin dealers into goblin black market magic dealers: they only get 20 gold per mage card deployed. That way they don’t get gold for themselves and slows down this particular strategy.
Additional Possible Nerf (I don’t recommend this)
Only allow drafting of one army type (elves, humans, etc) cards. This will slow down this strategy significantly as you have to wait for more and more gold to be able to hire elves. It also has an added benefit of requiring players to work together more: if an elvish player and a goblin player work together then the strategy works completely again. I don’t recommend this because it would be interesting in the future if more maps had players start with dual types of units (trolls and dwarves, etc). Reducing the flexibility of the game this way… idk I think it hamstrings the game from doing interesting things.
Additional Possible Nerf (I strongly do not recommend this)
Have all banner units (goblin spider pennon, human cyclops standard, etc) not allow other players to deploy to. Could potentially slow down this strategy. I don’t recommend this as how the ability works now allows people to work together more. Working together should be incentivized as much as possible. The potential of slowing things down is small and not a lot to gain by switching how this works.
Nerf Strategy 2 (not recommended)
Nerf the high elf mage, elder mage and goblin dealer a lot more. Possibly make them cost a lot more (both mana and gold). Make their abilities less powerful. In addition to standard nerfs maybe high elf mage power only works for units in forests? Or elder mages only work on creatures in forests? Maybe make it so that the player can spend up to X amount of mana for high elf mages and the damage done is 5 times the amount of mana spent? Then you have big bombs but you have to save up a lot to use them. That last suggestion looks attractive but I would strongly recommend against: it just slows down this strategy a lot but ultimately doesn’t really stop the player from dominating the map since elder mages still produce a lot of mana (in my case 1,300 or so) every 12 hours. It’s just frustratingly slow which has the potential to be boring for the players (they know they’ve won but need an extra 6 days of mop up)
I wouldn’t recommend doing this however, it’s better if the zombies evolve to change their tactics so that people don’t feel like their cards suck all of a sudden. Just that they now have to deal with this new problem given what cards they have.
Strategy 3
Rage quit making games because it is really, really hard and makes you want to cry sometimes 
One Last Important Note
@JayKyburz and @IHG-BlightedPea you have made an incredible game. I think everyone on the forums would agree with me on this. It’s fun, engaging to play with others and I can play it as much (or as little) as I want. Interesting strategy, fun collectible elements and good monetization (if anything a little too good… I’d honestly suggest making the free version a little bit more paired down). Honestly it’s great and for whatever it’s worth I think you should be proud of what you’ve created.
Finally: I tend to be very factual in my suggestions and having seen your posts/interacted with you a bit I can tell you are professionals at this. A professional is able to take feedback and say “yeah we should change things”. I’m not sure if either of you understand how that can be rare; there are a lot of creators out there that respond to criticism or suggestions by throwing it out/getting incensed that someone doesn’t understand their genius. You are clearly professionals that either don’t have that feeling or surpress it extremely well. Either way it’s pretty awesome and you should feel great about being so good at being able to handle suggestions and change the game to make it better.
This is honestly a great game and I want to do my best to make (often terrible) suggestions/help if I can to make it every awesome…r.