Inferno | Units Heroes III HD Edition Guide
Last update: 11 May 2016
Imp / Familiar
 | Attack: 2 Defense: 3 Ammo: - Damage: 1-2 Health: 4 Speed: 5 Cost: 50 Growth: 15 |  | Attack: 4 Defense: 4 Ammo: - Damage: 1-2 Health: 4 Speed: 7 Cost: 60 Growth: 15 |
Imps are without a doubt the weakest units in the game - they have low attack and defense values, their damage is ridiculous and with a spread between minimum and maximum damage. To make matters worse, they only have 4 health points. As always, it's not quality that matters, but quantity, so it's worth to build Birthing Pool to increase their weekly growth.
Upon upgrade, Familiars are given a boost to both attack and defense and quite a lot of speed points, making them no so useless as their basic form - their flaw remains their low health pool, which is left intact. Additionally, Familiars gain the ability of Mana Steal - each time the enemy hero uses a spell, Familiars will transfer 20% of the enemy hero spent spellpoints to their own hero.
Gog / Magog
 | Attack: 6 Defense: 4 Ammo: 12 Damage: 2-4 Health: 13 Speed: 4 Cost: 125 Growth: 8 |  | Attack: 7 Defense: 4 Ammo: 24 Damage: 2-4 Health: 13 Speed: 6 Cost: 175 Growth: 8 |
Gogs are Inferno's sole shooters, and as a 2nd level unit they are pretty balanced. Their attack and damage are well above average, but it comes with a price - low health pool and sluggishness are things that outshine their overall offensive effectiveness.
Magogs are one of those units that benefit greatly with their upgrade, but this time it's not because of their slightly improved attack and speed. The main reason for that is their special attack - instead of hitting one enemy unit, they throw a fireball (the same as with the Fireball spell, naturally) that deals damage to the targeted enemy and every adjacent creature. This attack is extremely effective, as most of the times you will be able to hit more than 1 enemy unit - the thing that you need to remember about is the fact, that their attacks can hurt your own units, even if they are immune to fire (like Efreets).
Hell Hound / Cerberus
 | Attack: 10 Defense: 6 Ammo: - Damage: 2-7 Health: 25 Speed: 7 Cost: 200 Growth: 5 |  | Attack: 10 Defense: 8 Ammo: - Damage: 2-7 Health: 25 Speed: 8 Cost: 250 Growth: 5 |
Hell Hounds are one of the best 3rd level units in the game (second only to the Griffins, thanks to their counterattack ability) - they dish out serious damage and are extremely fast, especially as a not upgraded and non-flying unit. Unfortunately, they have series of flaws, like low weekly growth and health pool, which prevents them from shining.
Hell Hounds are nothing before Cerberi- upgraded hounds are better in every aspect. They are given a boost to their defense, they are now faster and can attack up to three enemies simultaneously, if the enemies stand near each other (fortunately, the triple attack won't affect your own units). To make them even more awesome, they are given a special ability to their attack, which prevents enemy units from retaliating. Cerberi should be primarily used for offensive measures - their speed, coupled with damage and special properties of their attack will allow them to wreck havoc between enemy lines and your foe will have a hard time countering them because of their triple attack.
Given their extreme effectiveness, you should build Cages as soon as possible, to increase their weekly growth. Additionally, remember to frequently use Bless on them, as they have a huge spread between minimum and maximum damage.
Demon / Horned Demon
 | Attack: 10 Defense: 10 Ammo: - Damage: 7-9 Health: 35 Speed: 5 Cost: 250 Growth: 4 |  | Attack: 10 Defense: 10 Ammo: - Damage: 7-9 Health: 40 Speed: 6 Cost: 275 Growth: 4 |
After the perfect Hell Hound / Cerberus, the time has come for Demons, which, aside from their awesome design, are the weakest 4th level units in the game. Just look at their stats and compare them to previously described dogs - they are only a little higher, while still losing in speed big time. However, Demons are extremely cheap (being the cheapest 4th level unit in the game), so you won't feel betrayed by recruiting them.
The upgrade does not help them at all - they are given a slight improvement to health and speed, but that's it, no special abilities or resistances, nothing. You can easily neglect this upgrade and construct it only after you've built other, more important and useful buildings.
Pit Fiend / Pit Lord
 | Attack: 13 Defense: 13 Ammo: - Damage: 13-17 Health: 45 Speed: 6 Cost: 500 Growth: 3 |  | Attack: 13 Defense: 13 Ammo: - Damage: 13-17 Health: 45 Speed: 7 Cost: 700 Growth: 3 |
Pit Fiends are good, balanced units - they have high attack and defense attributes, and are able to deal massive damage, while average speed allows them to catch up to most units in the game. Their only flaw is a low health pool, which makes Pit Fiends quite vulnerable to enemy attacks.
Pit Lord upgrade hardly offer any stat boost over Pit Fiends, while they still cost a lot more, so to some it may seem as a useless upgrade. As always, the devil is in the details, or to be more precise, in their special ability. Thanks to that, they are able to summon Demons (yup, those Demons described above) from the corpse of an allied pack, which forces the enemy to focus their attacks on your Pit Lords - leaving them by may result in an infinite number of Demons returning on the battlefield. Thus this becomes one of your most important upgrades - thanks to a lot of cannon fodder (mainly Imps / Familiars) from Inferno, your Pit Lords will have their hands full all the time.
There are, however, to conditions on the Raise Demon ability - for each Pit Lord in the pack you can summon Demons equal to 50 health points. It means, that 7 Pit Lords can summon up to 10 Demons (because each Demon has 35 health points). Those values, quite obviously, aren't rounded and by, for instance, using 2 Pit Lords, you will be able to bring only 2 Demons back. The second condition is that you need the same amount of fallen units (in health points), because you won't be able to summon 20 Demons from a corpse of a single Imp.
Efreet / Efreet Sultan
 | Attack: 16 Defense: 12 Ammo: - Damage: 16-24 Health: 90 Speed: 9 Cost: 900 Growth: 2 |  | Attack: 16 Defense: 14 Ammo: - Damage: 16-24 Health: 90 Speed: 13 Cost: 1100 Growth: 2 |
The Efreet is a good 6th level unit, which easily keeps up with his counterparts from other towns. Their biggest merits are high attack attribute and damage, which, coupled with immense speed, allows them to get to the other side of the battlefield, and your enemies, during a single move - their only problem is, as always, relatively low defense.
Efreet Sultan gains a bonus to its defense, as well as a huge buff to speed, but the thing that makes them stand out from their "normal" cousins is their Fire Shield. Each time an enemy attacks the Sultan, 20% of the damage it dealt comes back at it. The enemy planning to attack this unit has to be on constant guard, as a moment of inattention can be fatal - sending a powerful unit, for instance Ancient Behemoths, or other 7th level creatures will easily wipe out the Efreet Sultan squad, but the enemy will sustain immense casualties thanks to the Fire Shield.
The Fire Shield effect can strike an enemy infinite amount of times and can cause quick a havoc - there's no point in sending melee units against them, but at the same time their speed allows them to easily reach the enemy's shooters. Your enemy won't have a choice - he/she will have to sacrifice some units to get rid of Sultans.
Aside from that, both "basic" and upgraded Efreets have invulnerability to fire magic, as well as they deal 150% damage when fighting against Genies.
Devil / Archdevil
 | Attack: 19 Defense: 21 Ammo: - Damage: 30-40 Health: 160 Speed: 11 Cost: 2700 + 1 mercury Growth: 1 |  | Attack: 26 Defense: 28 Ammo: - Damage: 30-40 Health: 200 Speed: 17 Cost: 4500 + 2 mercury Growth: 1 |
Devils are relatively weak 7th level units, especially given their somehow average stats, but they more than make up for it with their speed, as well as the ability to block an enemy counterattack thanks to "no retaliation" ability.
Arch Devils gain everything that the "basic" unit lacked - huge improvement to attack and defense, a little buff to health pool, and, what's most important, an immense speed increase, which makes them second fastest in the game. Thanks to that, they are ideal to get rid of enemy shooters, as they can easily reach the other side of the battleground in a single move - if you are not fighting against Castle city, they will be moving first, because from all the units in the game only Archangels are faster than them.
Additionally, both Devils and Arch Devils have a number of abilities their disposal. They move around by teleporting, meaning that their move won't be restricted by any terrain obstacles. Also, they decrease the luck of all enemy units by 1, as well as have a bonus to damage (150%) when fighting against Angels and Archangels.