Despite the fact that Avalon Hill has intended each of their new expansion boxes to only require the Game System to function properly, at times they have clearly encouraged the sharing of assets between boxes, or at least that naturally flows from it. Granted, back in '92, the intention seems to have been that customers were encouraged to collect "all four" (only 2 were released of course, officially) Hero themed expansions and freely use the upgraded characters from those (and share the Alchemist Shops, even though this was just the inner booklet cover at that time and no physical cards).
Here are the ones I'm thinking of, please feel free to add any more:
Haslab HeroQuest / 2021 retail Game System + ROTDM:
Rise of the Dread Moon included some tweaked cards (namely the Helmet and Hand Axe) that were updated in the 2022 (slim box) edition of the HeroQuest Game System from Avalon Hill. So if you don't have the newer edition you can refer to these.
Haslab HeroQuest (Heroic & Mythic)... Game System:
This set included a unique limited edition "Sir Ragnar Prisoner" as a special character to use in place of the Dread Sorcerer ("Chaos Warlock" in the original) to represent this character in Quest 2. Owners of WOM remake could use the included Sir Ragnar figure instead (though the figure is holding a sword, he can't actually fight in the basic rules).
Haslab HeroQuest (Mythic)... Game System & Return of the Witch Lord:
The Mythic tier included a unique figure of "The Witch Lord" to substitute for the Dread Sorcerer.
Haslab HeroQuest (Mythic) / Spirit Queen's Torment... Return of the Witch Lord:
"Kessandria" is described as a female lieutenant of the Witch Lord and the female Dread Sorcerer figure (stretch goal monster) can be used for her. The retail SQT has this same sculpt, in a translucent ghostly green color.
Haslab HeroQuest (Mythic) + Free digital Quest "Rogar's Hall":
Stephen Baker's online "Rogar's Hall" quest calls for the "Mentor" alternate wizard mini, which was unique to the Mythic tier in place of the Dread Sorcerer as a non-playable character. He pretty much just stands around though, representing Mentor's oversight. He could also be represented by the "Mentor" mystery tile if you lacked the special mini.
SQT / PoT / ATOH / ROTDM / JoD (also Hero Collections: Commander of the Guardian Knights / Rogue Heir of Elethorn / Path of the Wandering Monk) extra heroes:
These expansion boxes include extra heroes (Bard, Warlock, Druids, Knight, Berserkers & Explorers) that can be substituted for any of the four basic heroes and mixed and matched. However some quests (especially in KK/ROTWL) will be messed up if you lack specific heroes. Not having the Dwarf can make a quest much more difficult since the heroes will have to rely upon toolkits (if they have them) to disarm traps, although the Explorer has this same ability.
MOTM / FH / WOM / FL alternates :
These boxes include alternate sculpts of one of the four basic heroes. FL has alternates of all four. These could be used in any booklet, or could be used as an NPC, or as a stand in for "Double Image" spell in MOTM.
Both of these facts means that although not allowed by the default rules, a game could be played with more than four heroes, in theory, though it would make rounds take longer, and some resources would be divided more ways, and most quests would become easier (though a few, as in FH or MOTM would become more tolerable).
MOTM + any quest booklet:
In theory, the "Elf Spells" from Mage of the Mirror could be made available for the Elf to use in any adventure, including the Game System, however since they don't include any healing, it would be a much greater challenge to use these for a basic level Elf! Though not allowed in the default rules, a second Elf could join the party with enough spells to go between them as well.
WOM + any quest booklet:
In theory, the additional Heroic spell categories (Detection, Protection, Darkness) in Wizards of Morcar could be made available as options for the Wizard and/or Elf to choose from, though as they don't include healing (and several are more situational) they would provide a much greater challenge to basic level heroes. Also the "boons of heroism" offered with "Hopekin's Rest" are offered to be used (in theory) for any future quests played after this booklet.
FH / ROTDM / WOM / ATOH + MOTM:
Mage of the Mirror is an extremely difficult pack. It's suggested that if any mercenaries are "available to you" they can be hired in the group quests by the heroes from the expansions they are found in, and FH is specifically mentioned. ROTDM includes four mercenaries, WOM includes 12 and there's one Ogre mercenary available from ATOH.
MOTM + FH:
It's suggested that the Alchemist Shops (and their subsequent decks) can be shared between these expansion since otherwise most of the potions can only be purchased for use by one hero in the party. In theory its referring to any Alchemist Shop available to you, not just the ones in these two booklets (GS, FL, and ATOH don't have Alchemist Shops but the rest of the packs do, although ROTWL/KK/SQT and CoPD share the same one).
ROTDM + Any expansion with an Alchemist Shop (all of them so far except ATOH or FL):
Designer Doug Hopkins suggested on his blog that the "Alchemist" Deck could be used as a substitute for the Alchemist Shop of any expansion that contains one, as an alternate option. Of course JoD and WOM were released later and so include new items not found in it, but the main deck encompasses all of the rest of the items that could be found, giving new options though most of the prices are the same (except for the Potion of Lesser Healing).
Any Quest booklet + ATOH and JoD
The latter two expansions include "ranged" (called "archers" despite not all of the models using archery) versions of Orcs, Goblins, and Skeletons that Zargon is allowed to substitute whenever one of those monsters is called for in the booklet. In theory he could do the same with any book.
Any Quest booklet and Mage of the Mirror:
The original HeroQuest had four male hero miniatures. There were both male and female Elves provided in the Haslab edition of HeroQuest but most players today didn't have a chance to own that, but if they desire a male Elf mini to use for the original party in those quests, he's included in MOTM, using a pose from the original cover from 1992! Speaking of sex swapped figures... if you desire to have an "all female" monster squad in the game system, it's kind of possible to do that by raiding SQT and PoT (if you don't have the Mythic tier). There are also male and female goblins and orcs (of a ranged variety) included in ATOH (and some more of the goblins in JoD). MOTM has just enough of each that you can choose to have all male or female squads of elves or a mixed group.
Mage of the Mirror and Rise of the Dread Moon:
Between the two packs you have a "complete" set of Elven Furniture, replacing the Game System basic furniture (except there's only one table, the Torture Rack is replaced by the Arcane Prison, and there are no replacements for the regular open/closed doors).
You also get extra copies of the "Elven Archer" and "Elven Warrior" (swordsman) minis that could be used as additional enemies (or allies), not that you'd risk running out.
Crypt of Perpetual Darkness and Kellar's Keep and Return of the Witch Lord:
The retail version of CoPD is somewhat sparse, but if you compare the original version included with the Mythic tier, it used assets from both these expansions. The "random draw" for Spell scrolls makes little sense if you only use the included spell scrolls, but is much better with the ones from KK & ROTWL mixed in.
The entrance/exit doors are called for (and even appear in the app).
Several tiles from KK are used in Quest 3 (but with no specific extra mechanics added, they were deleted from the retail version).
There are also instances where more monsters of a certain type are called for than are included in the GS (and CoPD retail only adds the dragon figure).
There was a glitch in the printed retail booklet where the final boss had the same stats as the previous boss though it is corrected in the Companion App and the official digital PDF version.
Into the Northlands (uses Frozen Horror Assets) with Against the Ogre Horde:
This digital quest includes cards intended to be printed out and used in the Frozen Horror (at Zargon's discretion) as well as some suggested rules to mitigate the extreme difficulty (and let's be honest, player frustration) of this expansion. A "wolf ally" (animal companion) is called for, using the Zargon/Mentor "mystery tile" included in AH's Game System. But there's a single square "Wolf ally" in red plastic included with their edition of ATOH which has identical stats and fills in nicely for this character.
Too many doors called for in the Frozen Horror or Rise of the Dread Moon... add First Light:
In Avalon Hill's remake the doors are solid plastic rather than bases where you can just remove the cardboard (to simulate turning a "closed" door into an open one even if you run out). Here it's a little more awkward to re-use them, so if you really want to keep that immersion going stronger, you can raid "First Light" for additional doors (both open & closed)!
"The Dark Company" (from 1992's "Advanced Quest/Master Edition" European exclusive). Game System + FH / WOM + MOTM + ROTDM + FL
Although this set has not yet been remade in the Avalon Hill HeroQuest revival, this set COULD be played in the new edition using the Game System assets plus the Mercenary figures from either the Frozen Horror or Wizards of Morcar... AND sometimes too many examples of a certain type of furniture are called for on the board, if someone wished to follow what they see on the map more strictly, they can raid MOTM, ROTDM and FL to get extra copies of these furniture to place on the board (contrary to popular belief, Dark Company actually has the board reset once the heroes all travel off the edge via one of the doors, rather than actually intending for the use of four HeroQuest sets simultaneously.. it's more like the heroes are traveling through a cross section of the board, then returning and traveling another cross section, etc until they complete their goal). IF Zargon were wishes to use specifically entrance/exit doors for the "edge" doors, he might wish to also raid further sets like KK/ROTWL for these doors. Dark Company also makes reference to "Mentor" in a way that could be enhanced using the unique figure from the Mythic Tier set if desired.
Entrance Exit Doors (found in KK/ROTWL) used in JoD, ATOH, CoPD, FL.
While it's not strictly necessary to use the "Iron Entrance Door" (gray; formerly known as the "Steel Door" in classic editions) and "Reinforced Door" (brown; called the "Wooden Exit door" alternately) and can just use an ordinary closed door (and remove it from the board once all heroes have traversed it, unless they try to exit the quest early back through it, which is allowed in the Companion App at least) it is cool to have them available. ATOH includes the "Arena Gates" which can be used as open AND closed doors, but they cover two squares (most of the time this doesn't impact gameplay at all to use these instead).
First Light + Game System:
First Light uses cardboard standees for doors and monsters (except the frequently used boss Dragon), and flat cardboard tiles for furniture. Also the main gameboard uses thinner, flimsier material. Some may decide to use the board (except the reverse "Caverns" board which is used in almost half the quests). Using the Game System to "upgrade" the furniture and monsters to three dimensional models is pretty cool. And the cardboard doors can still be useful as in the "portal doors" called for in the second quest (with the "black void" in them). Another suggestion is to use the cardboard monsters as "dead bodies" (removing them from the plastic stands) and the furniture tiles help show the boundaries of furniture models (usually take up more space than the actual model does, overlapping squares) and provides a suggested painting guide! Alternately, the cards in FL provide some additional "flavor text" but the gameplay tweaks (which more frequently "nerf" the items or abilities) have something to be desired by some players. Some of the suggested additional in FL can also be implemented in the Game System if Zargon is willing. Most of these are revealed sporadically across other expansions but are organized here in one place officially for the first time.
Though not permitted in the general rules, FL has its own wizard mini and set of spell cards, so Zargon could allow two Wizards and/or two elves at once with all the cards included!
Other official rules that could easily be adapted elsewhere...
Jungles of Delthrak introduces the option to treat hero death saves differently, giving players an opportunity to be revived after death by a comrade, or automatically reviving if the board is cleared of monsters by at least one surviving hero.
Hero Collection: Rogue Heir of Elethorn + Into the Northlands
This mini expansion suggests "multiple attacks against the same target" work the same way as the Polar Warbear double attack as explained in this digital quest. In other words, every such attack, whether by a hero against a monster or a monster against a hero functions the same way, not just by Polar Warbears in FH or the Rogue against his enemies.
Dice (FH / CoPD / SQT / PoT / FL) + GS:
These sets all include their own set of combat dice and FH, CoPD, FL and the GS include their own movement dice. So in theory the sets could be combined to allow all four heroes AND Zargon to each roll a visually unique set of dice on their turn (though the FL dice are "bone" color which makes them not very distinct from the default white ones). FanRoll has released three HeroQuest deluxe tins of fancy combat dice but these are limited run products and may not be accessible to all. Additionally all four heroes could have their own movement dice set, though that leaves Zargon still having to borrow one or two when it comes time to try to resist a hero spell (except early copies of FL included reversed color movement dice which could then supply the remaining color... technically the Haslab version of HQ used a different shade of red plastic for its movement dice as well, vs. the later retail editions of the Game Systems). The Mythic set contained 12 white combat dice, which could easily be split between the heroes and Zargon though they are also the same colors.
Non-HeroQuest Game enhancements:
Avalon Hill's "Betrayal at House on the Hill" (3rd edition) and its various expansions include gray player character figures of the same scale as HeroQuest (as most Avalon Hill games do these days) but also various colors of rubber "boots" that can be attached to the bottom of a figure's round base to provide a quick visual contrast to the characters even if they are unpainted. These are the same type of rubber "boot" as used in CoPD for the Dragon mini. These boots fit all of the HeroQuest standard figures (not the double wide "surfboard" large monsters of course) and could be used to help differentiate characters or help keep track of a special status.







