Angband is a roguelike game looselybased on J. R. R. Tolkien's books set in Middle-earth, but with stuff from other games, mostly Dungeons & Dragons and Rolemaster, as well as some original content. It was intended as an enhanced port of Umoria, an earlier roguelike. The goal of the game is to descend into the dungeon and amass enough experience and loot to defeat Morgoth, the Big Bad of Middle-earth.Not as well-known as NetHack, but has a comparable fanbase. It is relatively easy to alter the source, so it has spawned hundreds of variants over the years, a few dozen of which are still in active development: one example is Z Angband. The latest version of Angband can be downloaded at http://rephial.org/.
Tropes in this game:
Artificial Brilliance: Monsters actively avoid tiles that you can see, opting to instead wait in the dark until they can pounce on you. They also learn your resistances (or, if you set the option, know them in advance) and will not attempt to use ineffective attacks repeatedly. In the variant/successor Sil orc packs try to flank you or block your escape routes, while archers will spead out and keep their distance - which is annoying and deadly.
Rods/Wands of Light in general, which light up a long line of tiles. If you rely in any kind of ranged attack, you'll need to spot monsters from as far away as possible, and these babies really shine in long corridors. You'd also be surprised by how many enemies are damaged by it in the early game.
Teleport away. You don't have to kill absolutely everything. It's far safer to punt a dangerous monster to the other side of the map and loot the treasure behind it than to try and fight.
Cast from Hit Points: Genocide/Banishment spell, which will subtract 1d3 HP for every monster killed from the spell. Also, casting a spell without enough mana could damage your CON (health stat) temporarily or permanently.
Companion Cube: Slime molds, a food item which many players name and keep as pets
Death of a Thousand Cuts: Explosive breeders. Most dangerous for low-level characters, but a sufficient number of them can cause problems even for higher-level players. If met at the start of the game, a Floating Eye can keep you paralyzed to the point that you starve to death.
Drone Jam: Anti-Summoning Corridors, the fancy name for player-dug corridors with a dead end the player sits on. They are meant to be used as a means to prevent summoning monsters from calling monsters behind you and surrounding you. While they are the most reliable means to deal with those, it can take a while for the Mook Maker to get in the player's range.
Drop the Hammer: Priests are restricted to using bashing weapons. Also, Morgoth's hammer Grond, which shatters walls all around when swung.
Explosive Breeder: Many low-level creatures, including worm masses, lice, and rats, each of which which have many annoyingcolourvariants. These can be ground upon to gain levels, but unless you're using a borg (a bot which plays the game) this is too dull to do for more than a few levels.
Final Death: It's a roguelike. You can savescum, but don't try to pass it off as a genuine win.
Game Mod: Few freeware games have such a large number of variants as Angband. oook.cz is the most known repository.
Gateless Ghetto: Built on top of Morgoth's fortress is a town consisting of six stores, a black market, a house belonging to the player, and a few ne'er-do-well townfolk, surrounded by an impenetrable wall. A few variants avert this by adding an overworld.
Guide Dang It: Don't go below 1000 feet (20th floor) without See Invisible. Don't go below 2000 feet (40th floor) without Resist Poison.
Massive Race Selection: Mostly Z Angband. The Z Angband variant Entroband has thirty-seven races and twenty-seven classes. Averted by a newer variant Sil, in which you can only choose Noldor (High Elves), Sindar (Grey Elves), Naugrim (Dwarf) or Edain (Human).
Randomly Generated Loot: The game uses this method for ego items and random artifacts. One starts with a basic item, like a Hard Studded Leather [7,+0]. With a numeric bonus, that might be a Hard Studded Leather [7,+3]. If it gets an ego, it might be an Elven Hard Studded Leather (increases stealth, detects orcs), a Hard Studded Leather of Resist Fire (reduces fire damage), or with two egos, an Elven Hard Studded Leather of Resist Fire! If it becomes a random artifact (or randart), it receives a unique name, like the Elven Hard Studded Leather of Felorith, and some random powers. Because this is Angband, most ego items and randarts look like average junk until the player identifies or psuedo-identifies the items.
Moria, the ancestor of Angband, has ego items but no artifacts.
Random Number God: Everything in the dungeon is randomly created. Surviving early on depends entirely on random luck.
Schmuck Bait: Greater Vaults. If you see a completely walled off room filled with treasure, run away.
Also, in ToME, don't equip that yellow ~ lying on the ground right away. It could be the Phial of Galadriel, or something really evil...
The Symbiote: Available as a class in Angband Variants for the Android/IOS.
Vendor Trash: Unidentified potions of apple juice, slime mold juice and water, which are given the same color qualifier across games (although no longer available in the latest versions). You can also sell other unidentified items as a cheap identification method. Known trashy items cannot be sold. Unknown items, however...
Video Game Cruelty Potential: The town level is full of beggars, harmless drunks, street urchins and mercenaries. The urchins of whom will try and steal from you. Guess what happens next. Even worse, the mercenaries can easily kill a starting character.
A fairly minor but entertaining example is selling broken swords/daggers and rusted chain mail to shops. The storekeeper will offer you one gold coin for it and then - surprise, surprise - it turns out said item has negative to hit/to dam/armor modifiers, thus making them worthless.
Warp Whistle: Scrolls of Recall. Also available as a cleric spell.
Weapon of X Slaying: One of many properties ego and artifact weapons can have is bonus damage against particular types of enemies. This is controlled by a set of independent boolean flags, allowing (in the extreme) the artifact sword Crisdurian, which has all the Slay X flags set (and has the damage dice to make it count).