Zombies aren't boring, use the imagination! Undead has lots of scope for so many ideas! An example of a completely unique system for the Undead is that they can have a funeral pyre where unwanted legions can be turned into a fraction of their resources, or all of the buildcost if at full health! Or a necromancer standing atop an short obelisk, who when units go near more undead rise to fill up the horde/heal them etc. etc. instead of a "boring well"
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