Clearly some resources are more abundant than others at different stages of the game. How about having a trading post of sorts (not talking about trading) where you can exchange your excess materials such as metal for wood? To balance things out the ratio of trade could be 2:1, and of course this should be fuel free.
Just a quick suggestion; In terms of equipment we could have 2 slots; one for clothing, such as gloves, glasses and vests and the other for weapon modifications such as extended magazines and ammunition mods.
To balance things out this feature can only be player enabled and once it is zombies gain a multiplier to both health and damage. Also in pvp killing a player whose survivors are utilizing 2 slots while you one would give bonus exp.
I have of course kept things simple in this post and would let the devs figure out if they should implement this strategy and how they would balance it out.
@Axearon What are you arming your survivors with? Pen knives? Melee was made to deal with the hordes since some weapons have aoe damage capabilities. Engineers, Soldiers, Leaders make very good 'tanks'.
Once you unlock the titan units things become pretty easy pretty fast. Make the lesser units useful for something other than meat shields, that would add an element of tactics to the game IMO.
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