I’m just putting this out (and duplicating my post elsewhere) because I need to address a very common misconception about Undead. Undead is very wonky because Undead basically has only one strategy available, despite the number of attempts to get UD strategic diversity, which is Crypt Fiends + DK.
People then complain that “ghouls should be usable”, or Lich / CL / DL should be usable, but it still ends up gravitating to Crypt Fiends + DK because that seems to be the linchpin of UD strategy. Except, if you think about it, that’s exactly why UD is the way it is.
DK means fiends. Coil doesn’t heal ghouls efficiently past level 1 (even footies get armor bonus to healing with Holy Light and can get a full heal from Level 2, if they’re somehow allowed to drop to 20 HP), and the entire Ghoul-centric playstyle is based on trading units as opposed to keeping them alive (which the DK is supposed to do).
People want to buff ghouls so they’d see use, but they don’t understand that ghouls are also a lumber harvester, and that ghoul builds mean that UD gets tons of lumber for expos / teching to tier 3 / ToTD.
Ghoul DK simply isn’t meant to be usable; it’s part of the UD racial design. At most, you can go 5-6 ghouls to get additional lumber income to cover Banshee + Stat + Fiend builds in T2, but DK is Fiend centric in T1 / T2. It’s the entire design of unholy aura; UA might look “weak” as an aura, considering that Endurance also gives attack speed upgrades, but what you’re getting with the Fiend DK combat is that all of a sudden you have a ranged unit that’s faster than other ranged units (Fiends under level 3 aura used to be as fast as Dryads), meaning it can kite with exceptional efficiency while dealing better damage than Dryads.
If you want to buff Ghouls, you have to think of them in combination with Lich, DL, and CL. The core Ghoul synergy isn’t even with DL, it’s with Lich, since Frost Nova ensures that while you’re likely going to end up losing ghouls in engagements, you’ll be able to turn it into a trade by slowing down enemy units so ghouls can surround and snipe them off.
Likewise, Ghouls aren’t intended as a main combat unit; i.e, they’re better thought of as a combination footman / peasant. The Ghouls aren’t supposed to be usable later on in the game; if the enemy gets AOE, you go necs and sacrifice the ghouls to provide corpses for necs to delete a expo and then switch to Necrowagon if the fight keeps going. or win the game there and then.
The entire point of Ghouls is that they’re supposed to enable UD transition ability; i.e, they get killed and replaced with Fiends / Gargs / Aboms / Necs. Trying to use them in late Tier 2 is suicide, because if you’re late Tier 2, you should have switched to Fiends / Necrowagon / Gargs by then, although a fast tech to Tier 3 with Ghoul Frenzy should allow you to switch to Aboms when they’re no longer viable.
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Also, on Ghouls = Lumber Harvester, here’s a fun part. Ghouls have a lumber harvesting cooldown of 1.35 seconds, while Peasants have a lumber harvesting cooldown of 1.1 seconds. In other words, Peasants harvest about .91 lumber per second, Ghouls harvest about 1.48 lumber per second, while Wisps harvest about .625 lumber per second.
Wisps, scaled to Peasant size, harvest then about .78 lumber per second, but they don’t have to carry the lumber back to base. Ghouls harvest about .93 lumber per second when scaled to Peasant size. In other words, Ghouls are approximately equal to Peasants when it comes to harvesting lumber, but they’re less food efficient (costs more gold than supply), or in other words, 5 ghouls = about 6 peasants, maybe 7 peasants when you consider that ghouls travel faster.
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If you must go fiends, consider going 5 ghouls instead of 3 ghouls and pushing the ghouls together with fiends when you attack (but not creep). It’s useful additional normal damage vs blademasters / etc, and the lumber can allow you to go late T2 with a ToTD for shees or necs alongside your slaughterhouse for statues. Upping fiend damage (but not ghoul damage) can also cause your opponent to make prioritization errors (i.e, ghouls deal less damage than fiends vs non-hero targets), and can potentially allow your fiends to meatshield for your high damage ghouls.