Series

Donkey Kong

10 games, 1981–2025.

Games

Mechanics

Mechanic	Donkey Kong 1981	Donkey Kong Jr. 1982	Donkey Kong Jr. Math 1983	Donkey Kong 3 1984	Diddy Kong Racing 1997
Boost pad					When idleRefresh
Difficulty ramp	Level and time
Drift boost					Held speed
Extra life	Once
High score	Table
Item distribution					Placed
Kill screen	Timer overflow
Rocket start					Graded press

A marked cell changed from the game before. “Uses” means the game has the mechanic, with no variant recorded yet.

Every claim, by mechanic and game

Concept	Donkey Kong 1981	Donkey Kong Jr. 1982	Donkey Kong Jr. Math 1983	Donkey Kong 3 1984	Diddy Kong Racing 1997
Boost pad					In the US 1.0 version of Diddy Kong Racing, a zip-pad surface sets a racer's boost timer to 45 when it's at 0, in the car, hovercraft, and plane routines alike, and a ground zipper object sets 45 for a grounded racer within its radius whenever the timer is below 15. A Nitro sets 35, 55, or 75 at its first, second, and third level. In the car's ground routine, while the timer is above 0 after the countdown, the throttle is held open and the factor the code calls `traction`, unless it's 0, becomes 2.0. Code
Difficulty ramp	Each board's bonus timer starts at 10 × level + 40, computed in 8 bits and capped at 80, and the readout shows 100 times the value: 5,000 on level 1, 6,000 on level 2, 7,000 on level 3, and 8,000 from level 4. The listings read MAME's `dkong` set (US set 1). Code Donkey Kong's internal difficulty, which the comments say sets the speed of fires and the behavior of wild barrels, is the level number plus a timer that steps once every 2,048 calls of its routine (256 × 8), capped at 5. Code
Drift boost					In the US 1.0 version of Diddy Kong Racing, a car's power slide starts in its ground routine when R is held, the stick is past 15 either way, and the car is going forward faster than 3 (the code's velocity below -3). While R stays held the routine multiplies the top-speed value by 1.1. Letting go of R, or slowing to a velocity above -2, ends the slide and sets nothing else. During a slide the car update clamps the stick to 50 either way, quarters steering into the slide, and adds 60 toward it; holding the stick 26 or more against the slide adds the update rate to a count, and past 80 the car spins out and the slide ends. In an atlas search of src/, every write to the boost timer belongs to a zip pad, zipper, the start, a Nitro, a magnet, a plane trick, the loop-the-loop vehicle, or a boss, so a slide ends without a boost. Mario Kart 64 instead charges stages toward a mini-turbo while the stick counter-steers a drift. Code
Extra life	Donkey Kong awards one extra life when the score reaches the DIP-switch setting: 7,000, 10,000, 15,000, or 20,000 points. A flag set on the award stops any further one for that player. Code
High score	Donkey Kong keeps a five-place high-score table in RAM at `$6100`, copied from a default table in ROM at power-on, each entry holding its place, its score, and room for a name. A player who places enters initials on a "NAME REGISTRATION" screen. Code
Item distribution					In the US 1.0 version of Diddy Kong Racing, a weapon balloon's type is set by its entry in the track's object list, with no roll: the code names five types, boost, missile, trap, shield, and magnet, which the decompilers' names for the all-balloons cheats pair with blue, red, green, yellow, and rainbow. A racer that touches a balloon takes its type. If the racer already held the same type with any left, the weapon's level rises by one, up to the third (level 2); otherwise it starts at the first. In a challenge the level stops at the second, and trap balloons start there; the Maximum Power-up cheat makes every pickup third-level, and CPU-driven boss vehicles collect none. The weapon and its quantity come from a table the game loads as an asset, two bytes for each type and level, so they aren't in the repo. A CPU racer's driving routine `func_80042D20` can also raise a first-level pickup by one, on a percent chance from the AI behavior table. Mario Kart 64 instead picks an item box's item in Grand Prix from a 100-slot row for the driver's place. Code
Kill screen	On level 22 the bonus timer's start overflows: 10 × 22 + 40 = 260, which wraps in 8 bits to 4. Because 4 passes the "less than `$51`" test, the cap never applies, and the board's timer starts at 4 instead of 80. dkdasm's comment pairs the starts 50 to 80 with bonuses of 5,000 to 8,000, so 4 stands for a 400 bonus. Code
Rocket start					In the US 1.0 version of Diddy Kong Racing, a race, challenge, or time trial starts its countdown at 80, and once the HUD signals the start each update takes the update rate off it; "Get Ready" shows while it reads 2 or more. A racer's first fresh press of A after the countdown drops below 80 decides its start boost. A press while the countdown reads 29 to 15 sets a boost timer of 4 up to 11 as the reading falls, half of 24 less the reading's excess over 14, rounded down (computed), and a press while it reads 14 or less sets 20 with a select sound; holding Z also counts a reading of 15 as 20. A first press while it reads 30 to 79 gives no boost and spends the chance. A Master CPU driver takes the start boost a human set, or 5 if none did, and an Expert one copies a human's if there is one. In the car's ground routine, while the boost timer is above 0 after the countdown, the throttle is held open and the factor the code calls `traction`, unless it's 0, becomes 2.0. Mario Kart 64 instead takes a press of A that begins within 8 race frame counts of its window opening (20 in Time Trials), while the kart's `THROTTLE` flag isn't already set, and every such start gets the Mushroom's boost timer, 80. Code