| Open Adventure, the C port of Crowther and Woods's Adventure 2.5 (1995), refuses any input of more than two words, answering “Please stick to 1- and 2-word commands.” It matches each word against its vocabulary on the first five letters only, ignoring case, and the instructions it shows a player who asks for them say to type “ne” for northeast, since “northeast” would read as “north”. | misc.c L567–571adventure.yaml L2920advent.h L22misc.c L401–402misc.c L384–385adventure.yaml L2861–2863 | Code |
| In Open Adventure (Adventure 2.5) the lamp's limit starts at 330 turns, or 1,000 if the player answers yes to “Would you like instructions?” Once per command, while the lamp is lit, the limit drops by 1; the check runs at the end of the cave-closing check, which returns before it on the turn the cave starts to close and the turn it closes. At 30 or below, fresh batteries in the room or carried, with the lamp also here, are used up and add 2,500; otherwise the game warns once. At 0 the lamp goes dark. | advent.h L27–32init.c L26main.c L1543–1548adventure.yaml L2935main.c L874–875main.c L884–901main.c L913–915main.c L1044main.c L1321–1326 | Code |
| Open Adventure (Adventure 2.5) refuses to take an object while 7 are already carried: “You can't carry anything more. You'll have to drop something first.” The bird doesn't count, a fix of the original's counting the caged bird as two items. | advent.h L25actions.c L386–388adventure.yaml L2945misc.c L672–674notes.adoc L57 | Code |
| Open Adventure's score routine (Adventure 2.5) tallies 430 points in its comment, 298 of them for treasures (computed: 60 + 14 + 224). Each treasure gives 2 points once found, and the rest of its worth (12 for treasures numbered before the chest, 14 for the chest, 16 for those after it) while it lies in the building in its found state, so a broken one doesn't pay. | score.c L18–35score.c L37–38score.c L44–58 | Code |
| In Open Adventure (Adventure 2.5), each dwarf that was already in the hero's location before the dwarves moved throws a knife, which hits if a roll of 0–999 is below 95 × (dflag − 2). The first volley always misses, at dflag 2; it raises dflag to 3, so each later knife hits 9.5% of the time (computed). Feeding a dwarf while food is here adds 2 to dflag, so 28.5% after one feeding (computed). Any hit kills the hero. | main.c L312–313main.c L437–444main.c L457–458main.c L469–473advent.h L198–202actions.c L716–719 | Code |
| Eric S. Raymond's history in the Open Adventure repository dates Will Crowther's earliest version to 1976 on a PDP-10 at Bolt, Beranek and Newman, and Don Woods's expanded 350-point version to June 3, 1977 at the Stanford AI Lab; Crowther and Woods's own line ended with the 430-point Adventure 2.5 in 1995. | history.adoc L16–17history.adoc L23–26history.adoc L28–30 | Code notes |