Frog Knows was the first public release of Angband. A fork of umoria developed by students at Warwick University, it expanded on its parent game in a number of ways which added excitement and variety to the game. The town level was expanded to include a home for the player to store items for safekeeping, and the huge variety of unique monsters and special artifacts which form the backbone of the content for most versions and variants were introduced. Powerful base item types like dragon scale mail, blades of chaos and scythes of slicing were also added to the game. The superpowered Dunadan and High Elf races were added to the game, and the number of spellbooks for each class was expanded to match the higher character levels attainable and larger dungeon.
The large variety of elemental damage types seen in later releases exists here in a rudimentary form; the corresponding breaths and resistances are already in the game, but the high elements themselves are not present as distinct projection types; the breaths instead use hacks based on the "missile" damage type. Internally the code is much like umoria, and lots of internal license statements comments and variable names reflect this much as later variants often hew closely to their parent codebases.