EXPLOIT: SPY too powerful

I wouldn't call this an exploit really, just a badly designed and very overpowered unit. My suggestion is to remove the AOE and make their ability single target only.

The damage is not a problem, but the early availability is. Later in the game units tend to have hitpoints so high that even 200 damage doesn't dent them, and then the army of spies dies to the counterattack. For instance, in my current game i am using archer units that have over 600 hitpoints with almost 200 attack, and that's still not maxed out.

The fact that the soverign/champions never have good hitpoints like large unit groups makes the imp power too strong. The power to crush enemy spellcasters before they can cast back only damages an already limited magic system.

It is certainly a bug with the infinite area, always ten damage regardless of defence, and it can be used against creatures like darklings meant to be immune to offensive spell targeting.

This has been discussed before.  If they made it a single target 10 true damage spell it would be more reasonable.

Tend to agree.  Single target damage or reduced aoe damge to 3 or 4. 

Just FYI you can hit darklings with any aoe spell, just not target them specifically.

I think for game balance, there should be stacking penalty for invoking same spell multiple times. That way people are encouraged to use different spells each turn, or at least pick different one after 2nd or 3rd time. It would encourage variety and reward people who have wide arrangement of spells.

IM not a fan of the AOE (hit everything) true damage spells.  Get rid of them from the game, even from the powerful end game demon units. The fact that the spy gets this ability relatively early on just exacerbates the cheese.  I learned that my demons were far more deadly split up into individual units killing everything on the field at once, than they were grouped together.  No opposing army can withstand that, and I certainly wouldn't like it if it were used against me by the AI.

I used to agree that the vigilant demon was way over powered, and then I went up against them with an actually powerful group of units. The average hp of a party is around 20 to start and by lvl 3-4 is up around 60. I have played a game where I had one stack with 2000+ hp, meaning you would need about 20 uses of arcane doom to take them out in the first round. Since a VD is basically worthless after casting arcane doom, this unit is only overpowered at the very beginning of a game. While I might agree that Arcane Doom might be better as a 3x3 aoe spell, the damage is not nearly as insane as rain of stones can be when cast by a lvl 15 shrill (which I have seen).

You can easily destroy any stack on turn one with VMs.  Once they hit level 5?  Or six maybe, they get an extra point of mana, and they will get there by the time you have that 2000hp stack, and they cast twice a round.  That's 20 damage to every unit per VM on the first round.  Its ridiculously easy to get up to 10 or more VMs, all you need is one level two hero per VM.

Now Demons are even more ludicrous.  They can cast three or four times each, every round.