1 Hrrrm.  It's been ages since I've played any of the HOMM games, though I did spend a good bit of time on them when they first came out.  Don't know what happened there.

2 When you "retreat", you do not get the hero back. Instead, the hero (along with artifacts) reappears in your tavern, to be hired again. All the troops are lost.

The purpose of the "retreat" command is to preserve a good hero in defeat, not to cancel out of a battle.

You can also "surrender" when fighting another player, in which case you must pay some ransom gold, but get to keep all troops.

Even in defeat, heroes are not killed, and they never lose their level and skills. They will eventually be available for hire again, but not necessarily on your side.


Basic advices:
Nearly everything in the game can be right-clicked for help or vital information.

The troops available for hire, whether in towns or in map buildings, are replenished at the beginning of each week.

Flaggable buildings on the map offer continuous benefits. Claiming them is essential to the game. These include mines (generate resources) or troop generators (which other than offering troop for hire, also boosts troop growth of the same type in your towns)

Much of the game is using your heroes to grab benefitial objects on the map. You'll need multiple heroes to do that. Later you'll also need to use idle heroes to ferry troops to your main hero.

Build town halls at the start of your game. They provide additional daily income.

There is no concept of maintenance or troop limits in the game.

The castle faction (humans) is for beginners. Inferno (demons) and fortress (swamp) are for advanced players.

3 Oh, I forgot:

When you start a game and hired one or two additional heroes, move their starting troops to your main hero. Only your main heroes need to fight battles and gain experience. You'll learn which objects on the map contain battles and which don't.

4 When assigning troops, use shift-click to split a stack.

During battle, you may want to turn on the hex grid and other displays. Click on the computer button at the bottom left for combat options.

No worry, HOMM is the easiest-to-learn big name strategy game ever.

5 cuc covered a lot of good points. A couple additional thoughts:

- If you are defending a town, you can not retreat. (Unless that town is a Stronghold type and has a special Escape Tunnel improvement built.) So be very careful about defending towns if you don't have enough troops to hold it. It can be better to flee and let the enemy have it, rather than risking the loss of a well-developed hero.

- If you right-click an enemy hero or a stack of monsters, you get a summary of their strength. This can range from "A few" (1-3) to "A pack" (maybe 20?) to "Lots" (50-70) all the way up to "Zounds!" (500+). Check this information on everything you can see to decide who you can fight and who should be left for later. At the start of a map, there will usually be quite a few enemies who are much too powerful to attack. These are positioned to block expansion into new areas of the map or to keep especially useful things out of your hands until you are stronger.

- These early strong monsters may also prevent AI heroes from reaching you, giving you time to develop your forces. Sometimes it is a good thing to have a big stack of something nasty around.

- The random monsters around the map grow in numbers with each passing week. So a stack of Minotaurs (random example) that shows as "Several" in week one might have grown to "A pack" by week 4.

- Each of the random monster stacks around the map have an attitude factor. Some of them hate you and will always fight. Others will offer to join you in return for gold. Still others will agree to join you because they support your cause. There is no general way to tell which is which from the map, but there are some spells and hero abilities that can help reveal attitude and even persuade monsters to a more favorable result.

Oh, and that dwarf town: dwarves are s_l_o_w. Terribly, terrible slow. And your heroes' movement on the main map is determined by the slowest unit in their army. I tend to leave dwarves at home unless I have nothing else.

Elves are cool, though.

6 As for factions, I agree that the Castle town (humans with pikes, archers, swordsmen, etc.) is one of the easier factions to learn and play. Pretty good town improvements available at reasonable costs, a decent and balanced army at lower levels, and with excellent high-end units.

The Inferno (demons) is more of a mid-range faction. I would also include Rampart (dwarves and elves, magic forest town), Dungeon (subterranean critter town), and Necropolis (the undead) in the middle difficulty group.

The tougher factions, at least for my play style, are fortress (swamp town), tower (snow town of wizards, very magic oriented), and especially stronghold (orcs).

All town types can be powerful if you can develop them and learn to make good use of their creatures. But some are definitely easier to learn than others.

7 All this Heroes discussion motivated me to crawl into the depths of my closet and pull out the old media folders.  I have Heroes III and V, but not IV for some reason.  It will be interesting to see if I can get III installed and patched up to where it will play, or if your version has something special to it.

8 Well, the HOMM3 which is being sold by GOG includes the Armageddon's Blade expansion pack and the Shadow of Death expansion pack. For whatever that's worth. (For me it was worth $5, which is what I paid.)

9 The expansion packs add a new town type, the Elemental Conflux, which is built around elementals and other "neutral" creatures. If I am remembering correctly, it also adds multi-part artifacts (such as the namesake Armageddon's Blade) and improves support for more elaborate quests. There are also new campaigns and maps to play. A pretty good deal for $5, if you like the base HOMM3 gameplay.

Another option to consider if you enjoy HOMM3 is Heroes: Chronicles, which I just picked up from GOG myself during the sale. There are 8 "chapters" each of which seems to be an 8 map campaign centered around one of the 8 town types. The whole thing is linked together as one big storyline. There are a few new creatures, but otherwise it is a standalone version of the HOMM3 engine that plays the new campaigns. (No additional maps or choose your own game options, just the campaigns.)

I have played the first 3 maps so far and have enjoyed it, even if the first chapter is about my least favorite town type: Stronghold. :-( Beware the might of my orcish armies!