Demons possess perhaps the most valuable skills of all: they train their creatures to summon new demons on the battlefield. This is called opening a gate. Each unit can do this once per battle and bring in reinforcements equal to 25% (at higher skill levels — 30%, 35%, 40%) of its strength. These become a separate unit; if all of the demon's unsummoned troops are destroyed, the summoned ones will vanish on their own. In any case, they leave you at the end of the battle.
Mark of the Damned — a spell that deals damage to a creature if it moves, attacks, or takes any other action. The additional abilities described above further enhance the effect of the mark.
Hellfire — a 30% chance for any attack by creatures to deal an additional fire strike, depending on the strength of the creatures and the hero's spell power. Mana for this operation is deducted from the hero, making it quite costly.
Soul Eater — mana restoration through the consumption of corpses. When Hellfire is present, this is a necessity.
Call of Urgash — reinforcements from hell arrive instantly.
Inferno Units:
1. Imp, own and devilkin.
This little weakling is present on the battlefield not to fight, but to "work" with enemy mana. The Imp simply eats it, while the same carefully brings it to you. Therefore, imps must be upgraded before the first encounter with an enemy hero!
Sames fight reasonably well, too... but they are very expensive. Since their ability is useless in battles with neutrals and they have few hit points, one must be careful with them.
As for the devilkin, this new "little imp" is slightly better protected and runs a bit faster. But the main difference is that while the same gives stolen mana to the master, the devilkin distributes it among fighters capable of casting spells. As is known, only cave demons and lords among the hellish hordes can do this; however, their spells are quite useful. If there are none in the army and none are expected, this novelty will be useless. In other respects — who knows? And if you have druids or archmagi at hand...
2. Demon, fire demon, and greater demon.
Try to find a single second-level creature that is worse than an ordinary demon! This wretched thing is good for nothing; kick it with your feet, you won't miss it. Its only ability is rage (enhanced upon the death of an ally).
If upgraded to a fire demon... well, in this form it at least looks like something. Additionally, it learns to deal explosive damage to all enemies around itself. To be blunt: without acquiring fire, a demon is good for nothing. If there is an opportunity — upgrade; if not — spend these creatures on whatever you want, you won't miss them. The greater demon is slightly better. Many were annoyed that these slow creatures never managed to reach their destination in time. Therefore, experiments were conducted in which some of the lesser demons were stripped of the right to explode and given a jump instead. The greater demon flies toward the enemy even across the entire map — and receives an attack bonus of 10% for each cell traversed (was the bomb replaced by a catapulting device?). However, the landing is apparently not very soft, and after its strike, the aviator receives a double counterattack.
3. Hellhound, cerberus, and fire hound.
The dog runs briskly across the battlefield and attacks twice as often as other thoughtful characters. And if it is upgraded — enemies stop responding to it, and it hits three squares at once. In general, not bad.
The fire hound is a weaker beast than the cerberus, slightly better protected — but possesses fire breath like a dragon. This means that it is useless to shield shooters with melee units — the attack hits both the immediate target and the target directly behind it. At the same time, it has three heads, just like the cerberus, and three attacks as well.
However, one should not immediately succumb to euphoria: this property is important only in battle against organized heroic armies. Neutrals do not know how to shield themselves from a charge, and as a result, fire breath triggers less often than desired. But -1 to damage always tells.
The dogs must be upgraded, because then they live much longer. They are fragile; don't put them under a counterattack...
4. Succubus, demoness, and temptress.
And here is the most pleasant news! The succubus is one of the best shooters, who also knows how to respond to shots (a unique ability!). However, hit points are low. But true potential is revealed only upon upgrade: then the demoness pleases us with nothing less than chain lightning!
But beware: if you lead mortal spawn with you instead of using exclusively unholy power, the chain lightning, once unleashed, might accidentally fail to distinguish and blast your own. It recognizes demons...
As for the temptress — she is a special case! It's a bit disappointing that succubi do not engage in their direct work — seduction. The temptress will fix this: she can fully subjugate an enemy unit once per battle (duration depends on the number of temptresses). However, while controlling the enemy, they cannot move and do not shift on the initiative scale. They themselves cannot be subjugated. In doing so, they lose a chain shot, so the choice is again not obvious at all.
5. Hell horse, nightmare, and steed of the underworld.
A worthy and incredibly fast combat unit. A unicorn is probably tougher, but does not race across the field as swiftly. With a decent chance, the horse's attack forces the enemy to retreat; in this case, the enemy does not respond and runs to the edge of the map, losing all accumulated initiative (!). This means that with a couple of units of such horses, you can give the enemy a real run for their money; not to mention that they easily break through defensive lines.
And if upgraded to a nightmare, it becomes even faster and more powerful, giving enemies -3 to morale within a three-cell radius around itself. Considering that it is large in its own right — this is a significant area.
As for which is better — the steed of the underworld or the nightmare — that is a difficult question. Instead of an aura of terror that lowers the morale of nearby enemy troops, the steed of the underworld simply burns them with its aura. At the start of each turn, any neighboring unit loses ten hit points for every fire horse nearby. Furthermore, the new breed of hell horses hits harder. The choice, however, is not obvious: against a good leader or, say, a necromancer, the steed of the underworld is better, but against an enemy who is not too high-minded and yet alive, perhaps the nightmare is better.
6. Cave demon, cave lord, and cave spawn.
A huge creature, and a mage to boot — it casts fireball and reduces enemy defense. True, in close combat it's so-so, but does that matter much? But again we realize that its potential cannot be unlocked without upgrade, at least to a lord. In this case, it receives a new spell — meteor shower, and, most pleasantly, the "shearing sword": this thing guaranteed kills at least one creature during an attack or counterattack. Imagine how wonderfully you can play around with dragons!
But still, do not rush to absolutely upgrade the cave dwellers (how do they fit in a cave given their size?!): for the upgrade hardly affects combat qualities, and fireball magic is generally sufficient. The wild variety of cave demon, called spawn for some reason, is much stronger in attack, slightly better protected, healthier, and also deals huge melee damage to large enemy units: two hit points for each opponent in the unit. However, the shearing sword that guaranteed killed one opponent is gone — against dragons and their ilk, the spawn is weaker than the lord. But — it does not cast spells! At all! As a weak consolation — 50% magic resistance. Not bad, but when only one unit in the army is protected from spells, it doesn't save you that much. Spawn are mainly used when the enemy has crowds of weak creatures.
7. Devil, archdevil, and archdemon.
The famous teleportation of devils is no longer as powerful as it once was: it is limited by distance! Yes, a devil can easily jump over a wall or a rock, but what's the point?
Upgrade does not make the devil stronger (only healthier), but gives him the right to revive killed cave lords. This creates a good, but very expensive combination. Therefore, do not rush to pay same-fold — likely, you will need the devil more in melee. And he is not worth such money. Can you believe it — more expensive than a black dragon! For what?!
The archdemon is not much better. Slightly slow but more powerful, this competitor to the archdevil cannot summon cave lords, but can teleport troops to himself — both his own and others'. To do this, they must be within his movement range. The ability is curious, but difficult to apply.
http://www.gamer.ru/heroes-of-might-and-magic-v-poveliteli-ordy/fraktsiya-inferno
Added after 7 minutes
Heroes of Might & Magic 5 (HOMM V): Tip (ballista tactic)
Playing as Inferno, choose the hero Deleb — (since this hero has a ballista + this ballista has explosive shells).
Then develop the hero's level to 3 or 5. (be sure to choose the "ballista" ability + develop "engine management" to the end). Then buy only seven imps. (the rest of the army can be bought by another hero). Then distribute the imps — one per cell.
Now all seven cells of the hero are occupied. When attacking the enemy, run around the battlefield with the imps, and destroy troops with the ballista and the hero. At early levels, this method greatly helps to defeat the enemy without losses.
Deleb, Iron Maiden
Deleb — one of the generals who were tasked with making Kha-Beleh's prison more convenient. She succeeded by inventing complex machines. Deleb believes only in her mechanisms, not in fickle demons whose loyalty is based on fear of her machines and fear for their own lives. For this, envious people call her the Meat Grinder.
Iron Maiden: A projectile fired from the ballista explodes like a fireball upon impact. The shock power of the fireball increases by +1 unit for every four hero levels.
Added after 18 minutes
Video Reviews
Interesting Inferno features
https://www.youtube.com/watch?v=PbOSXEYhWxc
Heroes 5 - Inferno, battles against AI # 1
https://www.youtube.com/watch?v=LUL75Pv640M
HOMM 5 [GUIDE] - Choosing Inferno creature upgrades
https://www.youtube.com/watch?v=cfrNu8YBUFQ
