Chaos Strikes Back - really dig its take on level design - the game starts at a middle level with 4 different paths going down or up (openness ftw), at another middle level there's a crammed-with-puzzles-room where all these 4 paths converge (and separately continue afterwards), the paths also intersect here and there; I remember accidentally killing a dragon by falling at it through a hole (I did the same in Dungeon Master, though there it was intentional through a sorta time stop item IIRC), also finding a key after killing a thief who stole it from me about 4 levels higher (played on Amiga 500+ btw
)
Wizardry 7 - probably my joint all-time favourite - despite limited tileset variety, the game manages to present seriously colourful set of locations thanks to distinct text descriptions, NPCs, enemies, puzzles and level design, comes with very solid character progression + itemization and sports to this day not quite matched (AFAIK) rival adventurers element, it's also very open and personally I really dig that some of the puzzles require items/knowledge found in a completely different part of the world, all the above + addition of skills like diplomacy/swimming/climbing/mapping makes this game the most feature-complete dungeon crawler there is, in my book; if it wasn't for slow mana regeneration, way too frequent random combat encounters, random stat increases on level-ups and few puzzles being way too unintuitive, I wouldn't hesitate to call this a perfect dungeon crawler (someone put together a pretty cool map of the gameworld, btw:
http://www.zimlab.com/wizardry/images/Wizardry7-Mapd.png)
Wizardry 8 - along with Wizardry 7 my favourite; compared to its predecessor it's not as rich in terms of puzzle and perhaps dungeon amount/variety, and the rival adventure parties element is severely simplified, but in my book the game quite manages to make up for it by its own specific strengths, which include really well put together character progression (easily my favourite as far as dungeon crawlers go), effective atmosphere boosters in forms of music and sound design, voiced NPCs with answers to surprising amount of topics and, at last but not least, voiced player characters (including joinable NPCs AND player generated ones, in which case the game offers a fair amount of distinct personalities to pick from); combat encounters taking generally too long to resolve, along with too fast enemy respawn rate, are the game's only real flaws I can think of; thanks to its character progression/personalities and
relatively solid production values this is my go-to game when I'm in the mood for dungeon crawlers (combat density and slowness is notably less of an issue on replays), which happens about once a year
Dark Souls 2: Scholar of the First Sin - this stretches what one usually thinks of when dungeon crawler genre comes up I guess, but personally I think it's pretty much in the same ballpark as Arx Fatalis or Ultima Underworld which are both games I think people wouldn't have much problems to classify as dungeon crawlers; regardless, this is easily my favourite "Souls" game, edging out the others mostly thanks to its combat mechanics, character build + area variety and general level of what I'd characterize as playfulness (NPC summons/invaders using gestures, in-world difficulty settings including host of possible NPC summon helpers, a joinable "covenant" that makes the game more difficult across the board and a possibility to make a specific area more difficult - which occasionally includes a new enemy set up); one aspect I'd like to point out, which personally I consider genius, is that melee weapons are diversified not only by stat (damage, speed, damage type, counter damage) and physical (length) properties, but also by inherent movesets (which differ not only between weapon categories, but also within them) - "gamey" feature or not, I'm finding this to be perhaps the biggest factor making the series (and this game in particular) head and shoulders above other cRPGs featuring action melee combat; it's also the only game in the series (AFAIR) which retains full one-handed movesets for weapons wielded in left hand, which, along with "powerstance" feature (special moveset for dual wielded weapon combinations), makes this by far the best dual wielding action cRPG melee combat in my book; also, voice acting in this game is fantastic; the game's (and the series') biggest flaw is some of the mechanics being needlessly obtuse
Legend of Grimrock 2 - the first game already surprised me by not being just reliant on nice visuals, but also clearly coming with a lot of work put into puzzle design, however its successor pretty much made it obsolete - it has more diversified puzzles (including less reliance on finding small buttons), multiple dungeons along with exterior environments, underwater areas and multiple endings rewarding exploration/optional puzzle solving; I guess one might see the game as less focused compared to the predecessor, but personally I consider it to be another of the game's strengths since the relative lack of focus is mainly due to major increase in openness; also, a bit á la Wizardry 7, some of the puzzles are solved through exploration of different parts of the world, which I'm a big fan of; I think the game's biggest flaw is character progression which I found rather unengaging and it's the main reason why even though I had a great time on my first playthrough I don't really feel like replaying the game any time soon
The above would be my top 5, Wizardry 8 being number one I think.
Two games which just didn't make it would be
Arx Fatalis - atmosphere and most of the puzzles in the game rule, I also really dig the game's take on spells; some of the puzzles are fairly unintuitive/badly implemented and character progression is neither particularly interesting nor well balanced, AFAIR
Ultima Underworld - I still consider this to be the best example of a cRPG which managed to both push technological limits AND deliver a well rounded experience not reliant on production values; I've never actually finished this one - the one and only time I've played it was shortly after its release on holiday with a friend and since we were young, restless and not particularly well versed in ye olde English we had frequent compulsions to kill the game's NPCs which resulted in missing out on some vital clues, the farthest we got was standing on the game's final boss' head and hacking it for 20 minutes straight without causing any damage
I remember finding
Black Crypt good overall too, but somehow I got through its second half in a day which resulted in not enough memories present. The coolest thing I remember was an early boss monster that could only be killed by a weapon found at a level below/after the encounter. I'm also pretty sure I've missed some puzzles/solutions altogether since I got through the final combat encounters by cheesing the enemies at stairs, doing 1 or so damage per hit
.