Wasteland

01 · Characters

The NPCs, record by record

Fourteen people in the 42 maps can join the party. Each is a 256-byte character record kept in the map that holds them, laid out like a Ranger's and copied whole when they join ($A42C). Most of it shows on the character screen once they have joined. Two things never do: a skill outside the 35 that the maps test to know who is in the party, and the rule that decides whether they join at all.

The hidden skills are numbers 36 to 48, one to a character. The skills page lists a skill only when its number is below 36 ($11A7), and so does a Use, so nobody playing sees them. A check square that asks for one finds it all the same: the search for a skill reads all 30 pairs ($1392), and at difficulty 0 knowing a skill is enough, with no dice ($8EAE). Felicia, Jackie, Ralf, and Christina carry hidden skills that no square asks for.

Dan Citrine's skill, 37, turns up far beyond the courthouse. Four squares there ask for it, among them the cell where his father waits: He sees Danny and says, "Thanks for rescuing me, son. Here's the money. I must run now." Another 83 check squares in 27 other maps test skill 37 and nothing else, and 60 of them take CON when they fail. No Ranger can have it: the Ranger Center sells skills 1 to 35 ($8502), and no library in the 42 maps teaches one above 35. So for anyone else those checks always fail. Dan has the skill at level 255, so he passes them, at once at difficulty 0 and on any throw of 5 or more above it. Per Jorner's guide lists this among its cheats as a recurring error in the game's "scripting": with Dan in the first party slot he'll mess up or nullify many hazards in the game, ranging from humble cactuses to lethal traps (page 81). The first slot matters where the first conscious member is tested for the whole party. On map 1's cactus every member is tested, and on the kit's 6502 simulator the game's check code ($8E14) ran it 1,000 times for a party of a Ranger and Dan. The Ranger was hurt every time: You've walked into a cactus. The spines poke you and hurt a lot. Dan was hurt 107 times, each time on a throw under 5.

Nine of the fourteen join as soon as they are asked while the party has room. The other five, Mad Dog Fargo, Metal Maniac, Ralf, Mort, and Dr. Mike Scot, throw the open 2d6 first ($A435). Their side is (CHR + IQ) / 2, plus their rank, plus record byte +$31. The hirer's side is (CHR + IQ) / 2 plus CHR plus rank, plus the throw, and a throw under 5 fails whatever the sums. The manual says only that charisma affects how an NPC will react to you when you want to hire him or trade equipment (page 4). Per Jorner writes in his guide that he has never seen an NPC resist more than one recruiting attempt (page 49). On joining, +$31 becomes the hirer's CHR ($A492), and nothing else writes it. The next section is about what that number is for.

In a fight an NPC takes no orders ($B500). It picks a group in reach at random, and its own fire mode. With a gun that fires bursts, it fires a single shot when fewer than 3 rounds are left and a burst at exactly 3. With more, a number from 1 to 10 against a table decides between a burst and automatic fire ($B4F8), and the table is read by how many characters are not conscious: never automatic while all are, then 2 in 10 with one down, 4 with two, 6 with three, 8 with four, and always with five, six, or seven. The manual says only that NPCs don't always do as told in combat (page 12). Per Jorner's guide passes on a report that Christina likes to fire full auto a lot (page 50). The code gives her no choice of her own: the gun and the characters who are down decide, the same for every NPC.

02 · Refusals

Bug: every NPC is as obedient as the next

Each record has four bytes meant to make that character more or less willing: one for using a skill, one for an item, one for an attribute, and one for giving an item away. The check that reads them loses the byte before it is used, so the target is 15 for every NPC. Only Redhawk is different. His trade byte is 255, which is tested first, so he never gives an item away.

The check is $0D61. It reads the byte, refuses at once on 255, and moves the byte into X for $0867, which returns 15 + 5 × X. In between it calls $0795 to clear the target, and that routine leaves 0 in X as well as in A. So a request is refused on a throw under 5, and otherwise when the throw plus one number falls short of 15. For a Use, that number is the NPC's own byte +$31, the hirer's CHR at the moment of the hire ($8D8E). For a trade, it is the CHR of the character taking the item ($0F70). With a CHR of 10 or more only the throw under 5 is left, one request in nine with fair dice and 13.1% with the game's, and that is the same for every NPC, Redhawk's trades aside.

The bytes still move. A refusal on a throw under 5 raises the byte by one, up to 10 ($0DA2), and a request carried out lowers it one time in 20 ($0D92). A hire lowers the three Use bytes by one for every 4 points the hirer's side beat the NPC's ($A496). Nothing reads them except the test for 255.

The manual promises more. NPCs don't always trade something when you ask them to, it says (page 12), and they have a mind of their own and may not always want to give their items away (page 6). Per Jorner's guide says that they sometimes refuse to trade away equipment or perform an action, and that over time they become less prone to rebellion (page 49). On the C64 the bytes that would do that go up and down, and the check never reads them. The guide is right about Redhawk, who will never trade anything away while conscious (page 52): an NPC who is not conscious is not asked ($0F63).

03 · Creating a character

Bug: the attribute roll that loses its best dice

A new Ranger's attributes are meant to be the best three of five dice. A slip in the sort loses the best dice instead, and the roll averages barely more than three dice would.

Creating a character at the Ranger Center rolls ST, IQ, LK, SP, AGL, DEX, and CHR, then MAXCON as one more roll + 18 ($7FDD). Each roll throws five dice into five slots, the first in slot 4 and the last in slot 0 ($8382). Then an exchange loop moves larger dice up into the higher slots, and the roll adds slots 2, 3, and 4 ($83B0). Sorted properly, those would be the best three of five.

The sort goes down from slot 4 to slot 1. Each pass loads the die in its slot once ($8397) and compares it with every slot below. When a slot holds a larger die, the two change places. The pass should now go on with the larger die it has just taken in. Instead, the branch at $83AB goes back to the compare, so the pass keeps comparing the small die it loaded. A second exchange in the same pass then writes over the larger die that moved up, and the small die ends up in two slots. Thrown in the order 1, 2, 3, 4, 5, the slots end as 1, 1, 1, 1, 5, and the roll is 7 where the best three make 12.

Over all 7,776 throws the roll averages 10.62, barely more than three plain dice at 10.5, where the best three of five would average 13.43. The roll comes out lower than the best three in 72% of throws and is never higher, so a new Ranger's seven attributes lose about 20 points between them on average. Watched in the emulator, 32 rolls at the Ranger Center ended slot for slot as the loop predicts, and 21 of them came out below the best three of their dice.

04 · Promotion

Nobody is promoted past rank 181, Supreme Jerk

A Ranger is promoted at the radio once the experience reaches 512 × k × (k − 1) for rank k. Experience is a 24-bit number, and from rank 182 on that threshold needs 25 bits, so the climb stops at 181, whose name is Supreme Jerk.

The radio tests each conscious Ranger in turn ($7F1B). Each rank costs 1,024 more experience than the one before: 1,024 to reach rank 2, 3,072 for rank 3, and 6,144 for rank 4. After a promotion the test runs again ($7FFF), so one call can promote a Ranger several times, with two points to spend each time. The threshold is worked out in three bytes, and one too big for them means no promotion ($7F46, $7F56). Rank 181 needs 16,680,960. Rank 182 would need 16,866,304, past the 16,777,215 that three bytes hold, where experience itself stops growing ($0825).

The table of names has an entry for every rank from 0 to 255. Ranks 2 to 11 have a name each, the names after that last two ranks, then three, then four, and from 131 every rank is General Argent but five: Imperial Scarscalp at 141, 1st Class Fargo at 151, Photon Stud at 161, Revenant Argent at 171, and Supreme Jerk at 181. Past 181 the five come round again every ten ranks to 231, and once more at 251 to 255, out of reach. When a promotion keeps the old name, the radio says the Ranger is still a Sergeant or a Captain ($7FBB).

The fans counted the same ladder. Rangers had told the HQ-Grid's Underground for years that there were 183 ranks, until K. Reimer showed (11 September 2010) that there are 181, as the C64's code has it. The site's list matches the C64 rank for rank, but for ranks 30 to 41: the C64 runs 2nd Lieutenant, 1st Lieutenant, Lieutenant, then Fireteam Lieutenant, and the list Lieutenant, 1st Lieutenant, Fireteam Lieutenant, then 2nd Lieutenant. K. Ballou (14 May 1998) found the cost of the climb with the Night Terror's 64,000, which will give each char several promotions the first time, but it gets to a point where you only get one promotion per 64000 exp. On the C64 the first such kill takes a new Ranger from rank 1 to 11, and from rank 63 on a kill no longer pays for even one promotion every time.

05 · Libraries

Bug: a library pays 64 skill points for a seventh level of Energy weapon

A library sells a level of a skill for skill points, at a price that doubles with each level. When the price is far above the points, the subtraction wraps round, and the Ranger walks out with more points than before and the level besides.

The price of the next level is the skill's base cost, 1, 2, or 3, doubled once for each level already learned, and 255 once that passes 255 ($CBF7). To train, a Ranger needs at least the base cost in points ($CA9C-$CAAB) and a level below the rank ($CAEE-$CAF2). The library then takes the price from the points and refuses only when the remainder has its top bit set, the sign of a negative byte ($CB03-$CB07). A price of 128 against fewer points leaves a remainder with that bit set, and is refused. A price 129 or more above the points wraps past 0 into the positive half again: a price of 192 adds 64 points, and a price of 255 adds 1.

The fans found the 255 first. M. Zier's super skills, on the HQ-Grid's Underground for the C64 and DOS, describe a library that shows a 255 to increase it, where a raise will add a skill point, up to your level, the rank. S. Hunter added (24 April 1998) that skills like Energy Weapon require only level 6, the level whose price is 192. Clem the Hick, on a C64, saw characters come away with 68-71 skill points: the 64 that a price of 192 adds, on top of the 4 to 7 they brought in. It didn't always work, which fits the rank rule: a level must be below the rank before a library sells it.