I am old time player of all the HoMM series. HoMM3 with Shadow of Death had armor sets where multiple pieces yielded better perks as new pieces were added. Dragon Armor etc. In this version, random maps do not include these armor sets like the original game. I am guessing I am out of luck. The campaigns offer SoD but I play random maps.

Random maps may not place the combination artifacts, but they do place the components that can be assembled into combination artifacts. You also may find those components for sale at the Black Market or in the Artifact Merchants. Once you have all the components, the game will prompt you to assemble them.

t Since I got the game from here, I have played two full random map (XL) games. There are single artifacts but I have never seen a piece of a combination artifact set. I will try again tomorrow and check the Black Market again. I played a lot of the old HoMM3 with AB and SoD and recall assembling many sets of artifacts.

I have in more than one game assembled Armor of the Damned and Cloak of the Undead King. In my most recent game, my lead hero had Armor of the Damned, Ring of the Magi, and Wizard's Well, though I prolonged the game a bit to collect the last part of the Well. It might have been faster to finish without it than to go out and retrieve the last piece, but I was expecting to need numerous castings of Dimension Door, and feared that without the Well, I would run out of mana before I reached my destination.

I believe I built Statue of Legion in one of my games. I don't think I ever built Power of the Dragon Father, though I have in several games gotten at least part of it. I have gotten parts of Titan's Thunder, but never the full artifact in one game.

The artifacts are randomly selected when placed on the map, and there are a lot of possible artifacts in the pool to be chosen. The pieces for combination artifacts can appear, but there's no guarantee any given artifact will be present, so there's also no guarantee that any given combination will be available when the map is first created. The Black Market and Artifact Merchants may or may not be useful in acquiring pieces as well. You might see only some parts, while the rest just didn't happen to spawn.