So say you've got a hero with Expert Necromancy. That's 30%. And you build a Necromancy Amplifier. That adds 10%. Is that adding a full 10%, to 40%? Or is it increasing by 10%, to 33%? I've been playing this game for almost twenty years and I just realized I have no idea haha. It feels like the former, but I don't know for sure.

yup they is they all add up to 40%

40%...?

:)

Is that it?! Wait'til you find artifacts in the field that'll boost the Necromancy skill even higher!

And if you have a special set, you can get it even higher... though I'm not sure how chances are you can get every item required for set/combination in normal game.
Also - add to it character with speciality in Necromancy. The jokes 'I can't hear you over my 7k skeletons' are real. ;)

getting the set is easier if you have towns with artifact merchats
or artifact merchant building on the map
since the stock resets either every week or every month cant remember witch

I thought about that, but it's still kinda random. Obviously better that hoping to find it on the map, but... :P

If a job is worth doing..... (Shadow of Death only)
Cloak of the Undead King (Amulet of the Undertaker + Vampires Cowl + Dead Man's Boots) give you Liches instead of skeletons when you have expert Necromancy. If you have Power Liches in your army and no empty spaces you get Power Liches instead. Also boosts Necromancy by 30%

Add to this
Bow of the Sharpshooter (Bow of Elven Cherrywood + Bowstring of the Unicorn's Mane + Angel Feather Arrows) and you lose range penalties for your Power Liches. Also boosts Archery Skill by (I think) 30%. You DID remember to get Attack + Archery in your build didn't you?

What was that about ...ven s...eton.? I can't hear you over my 13k Power Liches (for real, on an XL map).

Ok, I take it back. This is seriously more scary, though another set artifact adds to the bar... or is not really that hard to complete?

How easy is it to find all those artifacts on one map? I'm asking because I rarely play single maps, mostly campaigns only. So does such a set of artifacts happen often?

It all depends on your playstyle. Some prefer small / medium maps, and rush the enemy, "hey lookit me, I won in 2 weeks!" Personally I prefer large or Extra Large maps, and take my time exploring and perfecting. The longer you play, the more chance you'll find the artefacts you need.

Also, I always select "random artefact" when on the setup game screen. (Not random gold or resources). Then if playing, for example necro, if I find I have a Morale item, I just "restart scenario". Sometimes, some of the items are planted nearby by the mapmaker. Sometimes found on an enemy hero.

Each week, check the tavern for heroes that may have them as well. It sometimes happens that an enemy hero is killed by wandering monsters, and dies with all artefacts. Sometime worth hiring just to sell artefacts and make a profit.

My usual game time for L / XL maps is 6 - 14 months (gametime).

I only use the in game campaigns as a tutorial for new creatues, otherwise I stick to single scenarios. There are hundreds to download at http://www.maps4heroes.com/heroes3/maps.php and a wealth of info and downloads at
https://www.celestialheavens.com/homam-iii

Hope this helps. See above, plus, the campaigns are strictly structured, possible but less likely than a single scenario to find the items to make a set. If a set was to happen, it would be either because the designers specifically wanted it to be there for a plot reason, or if an artefact market (Academy / Dungeon / World Map) or Dragon Utopia spawned it.

It is possible in the map editor to make specific spells and artefacts unavailable, and I think the original designers made use of it for plot and balance. E.G. you wouldn't want the Wings of the Angel (enables flight across main map) if there were border guards to be overcome. Well, you might if you were a player, but not as a designer if it messes with the plot and balance.

Try some single scenarios, they can be as long as a campaign, and I find, often much more fun.

Honestly, I also prefer skirmish maps. Mostly because I always thought campaign is too hard, set on basically knowing EVERYTHING about the map to play it good. And also - yes, bigger maps. So you have time to build a lot of stuff, creat big armies to fight with.

So yeah - if played like that, for a longer time then smaller maps I still kinda remember - there are is a fair chance to get them.

Heroes and heroines never die in Heroes of Might & Magic games.

They just retreat back to the taverns.

:)

Heroes 4 would like a word with you. :P

Good point!
:)

Y'know, I've played and owned every single Heroes of Might & Magic game but I've never played nor owned Heroes of Might & Magic 4. Too bizzare for my taste.