Game 15 Unit 14 of 32 1 hr learning time

Real Combat

Implement the full combat formula with dice rolls, stat modifiers, and a damage loop until one side falls.

44% of Dungeons Of Dorin

Mark as complete Completed!

The combat screen is in place, but attacks do nothing yet. This unit implements the full combat formula: a random dice roll plus the attacker stat, minus the defender defence. Both sides trade blows each round until one side falls. The numbers from unit 1 — attack, defence, HP — finally drive real consequences.

The Program

5 REM === DUNGEONS OF DORIN ===
10 BORDER 0: PAPER 0: INK 7: CLS
20 PRINT AT 3, 4; INK 7; BRIGHT 1; "DUNGEONS OF DORIN"
30 PRINT AT 6, 2; INK 6; "Descend ten floors of"
35 PRINT AT 7, 2; INK 6; "darkness. Find the Heart."
40 PRINT AT 10, 2; INK 7; "Q/A = up/down"
42 PRINT AT 11, 2; INK 7; "O/P = left/right"
44 PRINT AT 14, 2; INK 7; "Press any key to begin"
50 PAUSE 0
60 CLS
70 REM === define stats ===
80 LET h = 20: LET z = 20: LET a = 3: LET f = 2
82 LET g = 0: LET e = 1: LET q = 0
84 DIM d(16,16): DIM v(16,16)
86 DIM j(5): DIM k(5): DIM l(5): DIM n(5)
90 REM === generate floor ===
92 GO SUB 1000
94 LET x = u(1,1) + 1: LET y = u(1,2) + 1
96 LET t = u(s,1) + 1: LET t2 = u(s,2) + 1
98 IF t >= 1 AND t <= 16 AND t2 >= 1 AND t2 <= 16 THEN LET d(t2,t) = 2
100 LET t = INT (RND * 3) + 2
102 IF t > 5 THEN LET t = 5
104 LET m = t
106 FOR i = 1 TO m
108 GO SUB 1600
110 LET j(i) = t: LET k(i) = t2
112 LET l(i) = 1: LET n(i) = 4
114 NEXT i
116 GO SUB 380
118 CLS
120 GO SUB 300
122 GO SUB 500
124 REM === main loop ===
126 PAUSE 0: LET i$ = INKEY$
128 LET t = x: LET t2 = y
130 IF i$ = "q" OR i$ = "Q" THEN LET t2 = y - 1
132 IF i$ = "a" OR i$ = "A" THEN LET t2 = y + 1
134 IF i$ = "o" OR i$ = "O" THEN LET t = x - 1
136 IF i$ = "p" OR i$ = "P" THEN LET t = x + 1
138 IF t = x AND t2 = y THEN GO TO 124
140 IF t < 1 OR t > 16 OR t2 < 1 OR t2 > 16 THEN GO TO 124
142 IF d(t2,t) = 1 THEN GO TO 124
144 REM check monster collision
146 FOR c = 1 TO m
148 IF j(c) = t AND k(c) = t2 AND n(c) > 0 THEN LET i = c: GO SUB 800: GO TO 160
150 NEXT c
152 LET x = t: LET y = t2
154 IF d(y,x) = 2 THEN GO SUB 600: GO TO 124
156 GO SUB 380
160 GO SUB 300
162 GO SUB 500
164 GO TO 124
300 REM === draw viewport ===
302 FOR c = -3 TO 3
304 FOR o = -3 TO 3
306 LET t = x + o: LET t2 = y + c
308 LET i = 1: LET i2 = 0
310 IF t < 1 OR t > 16 OR t2 < 1 OR t2 > 16 THEN GO TO 340
312 IF v(t2,t) = 0 THEN GO TO 340
314 LET i = d(t2,t)
316 LET i2 = 7
318 IF i = 1 THEN LET i2 = 4
320 FOR s = 1 TO m
322 IF j(s) = t AND k(s) = t2 AND n(s) > 0 THEN LET i2 = 2: LET i = 5
324 NEXT s
340 LET t3 = 3 + c: LET t4 = 11 + o
342 IF o = 0 AND c = 0 THEN LET i2 = 7: LET i = 6
344 IF i2 = 0 THEN PRINT AT t3, t4; " ": GO TO 370
346 IF i = 0 THEN PRINT AT t3, t4; INK i2; ".": GO TO 370
348 IF i = 1 THEN PRINT AT t3, t4; INK i2; CHR$ 143: GO TO 370
350 IF i = 2 THEN PRINT AT t3, t4; INK i2; ">": GO TO 370
352 IF i = 5 THEN PRINT AT t3, t4; INK i2; "M": GO TO 370
354 IF i = 6 THEN PRINT AT t3, t4; INK i2; "@": GO TO 370
356 PRINT AT t3, t4; INK i2; "?"
370 NEXT o: NEXT c
372 RETURN
380 REM === update visibility ===
382 FOR c = y - 2 TO y + 2
384 FOR o = x - 2 TO x + 2
386 IF c >= 1 AND c <= 16 AND o >= 1 AND o <= 16 THEN LET v(c,o) = 1
388 NEXT o: NEXT c
390 RETURN
500 REM === draw status ===
502 PRINT AT 8, 2; INK 7; "HP:"; h; "/"; z; "  "
504 PRINT AT 9, 2; INK 4; "AT:"; a; "  "
506 PRINT AT 10, 2; INK 5; "DF:"; f; "  "
508 PRINT AT 8, 20; INK 6; "FL:"; e; " "
510 PRINT AT 9, 20; INK 6; "AU:"; g; "  "
514 RETURN
600 REM === stairs down ===
602 LET e = e + 1
604 IF e > 10 THEN GO TO 1100
606 PRINT AT 12, 5; INK 7; BRIGHT 1; "DESCENDING..."
608 PAUSE 30
610 GO TO 90
800 REM === combat ===
802 LET i5 = l(i)
804 RESTORE 1500
806 FOR c = 1 TO i5 - 1: READ i$, t, t2, t3, t4: NEXT c
808 READ i$, t, t2, t3, t4
810 LET i4 = n(i)
812 CLS
814 PRINT AT 0, 0; INK 2; BRIGHT 1; "COMBAT: "; i$
816 PRINT AT 2, 0; INK 7; "Your HP: "; h; "  Enemy HP: "; i4
820 REM combat loop
822 PRINT AT 5, 0; INK 7; "A)ttack"
824 PAUSE 0: LET i$ = INKEY$
826 IF i$ <> "a" AND i$ <> "A" THEN GO TO 824
828 REM player attacks
830 LET c = INT (RND * 6) + 1 + a - t3
832 IF c < 1 THEN LET c = 1
834 LET i4 = i4 - c
836 PRINT AT 8, 0; INK 4; "You hit for "; c; "!    "
838 IF i4 <= 0 THEN GO TO 890
840 REM monster attacks
842 LET c = INT (RND * 6) + 1 + t2 - f
844 IF c < 1 THEN LET c = 1
846 LET h = h - c
848 PRINT AT 10, 0; INK 2; "Enemy hits for "; c; "!    "
850 IF h <= 0 THEN GO TO 1200
852 PRINT AT 2, 0; INK 7; "Your HP: "; h; "  Enemy HP: "; i4; "  "
854 PAUSE 20
856 GO TO 820
890 REM enemy defeated
892 PRINT AT 12, 0; INK 4; BRIGHT 1; "VICTORY!"
894 LET n(i) = 0
896 LET g = g + t4: LET q = q + 1
898 PRINT AT 14, 0; INK 6; "Gained "; t4; " gold"
900 PAUSE 30
902 CLS
904 RETURN
1000 REM === generate floor subroutine ===
1002 FOR i = 1 TO 16: FOR o = 1 TO 16
1004 LET d(i,o) = 1: LET v(i,o) = 0
1006 NEXT o: NEXT i
1010 LET s = INT (RND * 3) + 3
1012 DIM u(5,4)
1014 FOR i = 1 TO s
1016 LET u(i,1) = INT (RND * 10) + 2
1018 LET u(i,2) = INT (RND * 10) + 2
1020 LET u(i,3) = INT (RND * 4) + 3
1022 LET u(i,4) = INT (RND * 4) + 3
1024 FOR c = u(i,2) TO u(i,2) + u(i,4) - 1
1026 FOR o = u(i,1) TO u(i,1) + u(i,3) - 1
1028 IF c >= 1 AND c <= 16 AND o >= 1 AND o <= 16 THEN LET d(c,o) = 0
1030 NEXT o: NEXT c
1032 NEXT i
1034 FOR i = 1 TO s - 1
1036 LET t = u(i,1) + INT (u(i,3) / 2)
1038 LET t2 = u(i,2) + INT (u(i,4) / 2)
1040 LET t3 = u(i+1,1) + INT (u(i+1,3) / 2)
1042 LET t4 = u(i+1,2) + INT (u(i+1,4) / 2)
1044 IF t <= t3 THEN FOR o = t TO t3: IF t2 >= 1 AND t2 <= 16 AND o >= 1 AND o <= 16 THEN LET d(t2,o) = 0
1046 IF t <= t3 THEN NEXT o
1048 IF t > t3 THEN FOR o = t3 TO t: IF t2 >= 1 AND t2 <= 16 AND o >= 1 AND o <= 16 THEN LET d(t2,o) = 0
1050 IF t > t3 THEN NEXT o
1052 IF t2 <= t4 THEN FOR c = t2 TO t4: IF c >= 1 AND c <= 16 AND t3 >= 1 AND t3 <= 16 THEN LET d(c,t3) = 0
1054 IF t2 <= t4 THEN NEXT c
1056 IF t2 > t4 THEN FOR c = t4 TO t2: IF c >= 1 AND c <= 16 AND t3 >= 1 AND t3 <= 16 THEN LET d(c,t3) = 0
1058 IF t2 > t4 THEN NEXT c
1060 NEXT i
1062 RETURN
1100 REM === victory (placeholder) ===
1102 CLS
1104 PRINT AT 8, 4; INK 7; BRIGHT 1; "YOU FOUND THE HEART!"
1106 PRINT AT 12, 6; INK 7; "Press any key"
1108 PAUSE 0
1110 STOP
1200 REM === death (placeholder) ===
1202 CLS
1204 PRINT AT 8, 6; INK 2; BRIGHT 1; "YOU HAVE FALLEN"
1206 PRINT AT 12, 6; INK 7; "Press any key"
1208 PAUSE 0
1210 STOP
1500 REM === MONSTER DATA ===
1502 DATA "Rat", 4, 1, 0, 2
1504 DATA "Goblin", 8, 2, 1, 5
1506 DATA "Skeleton", 12, 3, 2, 8
1508 DATA "Troll", 18, 4, 2, 12
1510 DATA "Wraith", 15, 5, 1, 15
1512 DATA "Dragon", 30, 6, 4, 50
1600 REM === find empty cell ===
1602 LET t = INT (RND * 14) + 2
1604 LET t2 = INT (RND * 14) + 2
1606 IF d(t2,t) <> 0 THEN GO TO 1602
1608 IF t = x AND t2 = y THEN GO TO 1602
1610 RETURN

How It Works

Lines 830-840 handle the player attack. The damage formula is INT(RND * 6) + 1 + a + w - t3, where a is the player base attack, w is the weapon bonus, and t3 is the monster defence. The random component (1-6) simulates a dice roll. If the total drops below 1, it is clamped to 1 — every attack deals at least 1 damage.

Line 836 subtracts damage from the monster HP. Line 838 prints the result: “You hit for X!” in green INK.

Line 842 checks if the monster HP has dropped to 0 or below. If so, the fight is won and control jumps to the victory handler at line 890.

Lines 844-856 handle the monster attack. The same formula applies in reverse: INT(RND * 6) + 1 + t2 - f - r, where t2 is the monster attack stat, f is the player base defence, and r is the armour bonus. The result is subtracted from the player HP.

Line 856 checks for player death. If HP reaches 0, control jumps to the death handler at line 1000.

Line 858 updates the displayed HP values, and line 862 loops back to let the player choose again.

The Combat Formula

The formula roll + attack - defence is a classic RPG pattern. The random element (1-6) means the outcome is not purely deterministic — a weak character can occasionally land a strong hit, and a powerful one can whiff. The stats shift the odds. Higher attack means dealing more damage on average. Higher defence means absorbing more.

The minimum damage of 1 prevents stalemates. Without it, a heavily armoured player fighting a weak monster could take 0 damage every round, making combat risk-free. Similarly, a rat with 0 defence can always be hurt, preventing frustrating misses.

Victory and Rewards

Lines 890-906 handle monster defeat. The monster HP is set to 0 in the array, which removes it from the dungeon — the viewport renderer only draws monsters with HP above 0. The player receives gold from the monster DATA, and the kill counter increments. A brief victory fanfare plays before the screen clears and control returns to the exploration loop.

Try This

Log every roll. Print the raw dice roll, the stat modifier, and the final damage on separate lines. This makes the combat formula transparent and helps the player understand why some hits deal more damage than others.

Fight a rat with default stats. The player (attack 3, defence 2) against a rat (HP 4, attack 1, defence 0) is a gentle introduction to combat. How many rounds does it typically take?