Mario Party DS Mechanics Research

[Mathy]

This is a thread for documenting obscure mechanics in Mario Party DS. I originally started this in the Discord but wanted to move it here for visibility.

You are encouraged to reply with questions as well as your own findings! Everything known so far will be added to the OP.

Spaces (all boards)

Duel Spaces

The Duel wheel is based on the star count of both players. If the sum of both players' coins is >=1000, the "All your coins" option is replaced with "Half your coins."

Spoiler: Duel wheels

1. 10 coins / 20 coins / 20 coins / Half your coins / All your coins
2. 20 coins / 20 coins / Half your coins / All your coins / 1 Star
3. 20 coins / Half your coins / All your coins / 1 Star / 1 Star
4. 10 coins / 1 Star / 1 Star / 2 Stars / 2 Stars
5. 1 Star / 1 Star / 1 Star / 2 Stars / 2 Stars

Wheel	1	2	3	4	5
Both players have >=2 Stars	-	30%	-	60%	10%
Exactly one player has >=2 Stars	-	50%	-	40%	10%
At least one player has 1 Star, neither has 2	-	30%	70%	-	-
Neither player has any Stars	100%	-	-	-	-

There are 12 possible minigames that can be played on a Duel space.

Spoiler: Duel Minigames

Goomba Wrangler
Study Fall
Soccer Survival
Get the Lead Out
Trash Landing
Cheep Cheep Chance
Whomp-a-thon
Crater Crawl
Boogie Beam
Dust Buddies
Cyber Scamper
Soap Surfers

Bowser Spaces

Each of the 4 events has a base chance of occurring but will be silently changed to a different event if certain conditions aren't met.

Event	Chance	Note
Gimme Equality	10% (100% if the player has 0 coins)	Becomes Gimme Charity if the sum of all players' coins is less than 4
Gimme Charity	20%	Becomes Gimme Stars if the player has less than 3 coins
Gimme Stars	30%	Becomes Gimme Coins if the player has 0 stars
Gimme Coins	40%

If the player has fewer than 20 coins, Gimme Coins takes 10 coins; if the player has at least 20 coins, there is a 20% chance Bowser will still go down to 10 coins. He takes 20 coins otherwise.

Items

Shop Mechanics

Spoiler: Shop mechanics

Games are divided into 2 or 3 "phases" depending on how long the game is:

Game length	Phase 1	Phase 2	Phase 3
10	1-5	6-10	-
15	1-5	6-15	-
20	1-6	7-13	14-20
25	1-8	9-16	17-25
30	1-8	9-25	26-30

The items available from the shop vary based on the phase of the game and the player's placing. Items with are guaranteed to appear; items with are randomized, and each has an equal chance to fill the remaining slots.

Item	Phase 1	Phase 2 (1st-2nd place)	Phase 2 (3rd-4th place)	Phase 3 (1st-2nd place)	Phase 3 (3rd-4th place)
Double Dice Set
Triple Dice Set	-
Halfway Dice Block			-		-
Warp Dice Block
Snag Bag
Star Pipe	-
Block Detector	-	-	-	-
Grab Bag	-	-	-

Warp Dice Block

The Warp Dice Block can choose any blue or red space to warp the player.

Hexes

Spoiler: Hex drop rates

First turn only

Item	Chance
Coin Swap Hex	5%
Space Swap Hex	15%
10-Coin Hex	80%

Subsequent turns

Item	Chance
10-Coin Hex	10%
20-Coin Hex	20%
Coin Swap Hex	10%
1-Star Hex	30%
2-Star Hex	10%
Space Swap Hex	3%
Star Block	7%
Coin Block	10%

Star Spaces

Wiggler's Garden, Toadette's Music Room, and Bowser's Pinball Machine all use the following steps to determine the next Star Space:

1. Mark all Star Spaces players are standing on as used
2. If all Star Spaces are used, mark them all as unused
3. Pick a random Star Space that is unused, does not have a player standing on it, and isn't the same as the current Star
4. Place the Star at this space and mark it as used

Kamek's Library doesn't use star space cycling at all; see the board section for details on how the jars are spawned.

Hidden Blocks

There is one Hidden Block active at a time, always on a Blue Space. When a Hidden Block is found, a new one spawns on a different Blue Space. Using the Hidden Block Detector moves the Hidden Block to the player's landing space, regardless of what kind of space it was. The Hidden Block's content is randomly determined when the player lands on it:

Spoiler: Hidden Block table

Hidden Block type	Probability	Notes
Normal block (player can collect coins for 5 seconds)	70%
1 Star	10%
Coin Block (player can collect coins for 10 seconds)	5%	If the player has a Coin Block in their inventory, this becomes a normal block instead If the player is holding 3 items and none of them is a Star Block or Coin Block, this becomes a Star Block instead If the player is holding 3 items and one of them is a Star Block, this becomes a normal block
Star Block (gives 1-3 stars at random)	1%	If the player has a Star Block in their inventory, this becomes a normal block instead
Item Block (Gives items until inventory is full. Each of the 8 normal items has an equal chance to appear.)	4%	If the player is holding 3 items, becomes a normal block instead
Ztar (-1 Star)	10%	If the player has no Stars, this becomes a normal block instead

Minigame Selection

If any players landed on a non-red/blue space, the minigame to be played is chosen based on weighted probabilities, then teams are randomly assigned if applicable.

Spoiler: Minigame selection

Green	Blue	Red	4-player minigame	1-vs-3 minigame	2-vs-2 minigame
1	1 or 2	1 or 2	-	50%	50%
1	3	0	70%	30%	-
1	0	3	30%	70%	-
2	1	1	-	40%	60%
2	0 or 2	0 or 2	50%	25%	25%
3	0 or 1	0 or 1	50%	25%	25%
4	0	0	50%	25%	25%

Independent of the above, there is a 10% chance for the minigame to be a Battle minigame, as long as it is at least turn 3, the sum of all players' coins is at least 20, and the last minigame was not a Battle. "Last minigame" includes Duel minigames that happen during the turn, so a Battle can happen 2 turns in a row if a Duel happened during the turn. Each player in a Battle puts in coins equal to the turn number times 2.

Bonus Stars

Minigame Star

4-player, 1-vs-3, 2-vs-2, and Battle minigames count towards the Minigame Star. Battle minigames will count as a win as long as the player got at least 1 coin, regardless of how much they put in. Coin-collecting minigames will count as a win as long as the player collected at least 1 coin.

 

[Mathy]

Wiggler's Garden

Three Tulips

The tulips have a practically equal chance of having 30, 10, or 1 coin. There is a very slight bias towards the leftmost tulip having higher coin amounts (e.g. it's 34-33-33 for which one gets 30 coins).

Bank Bulb

The reward is based on the total X movement of the stylus. Every 320 pixels of horizontal motion = 1 coin. Letting go resets the counter for the current coin to 0.

Piranha Plant

The chance for the Piranha Plant's fireball to fail is based on the player's current placing:

Place	Chance to fail
1st	11%
2nd	21%
3rd	31%
4th	51%

(The constants used are actually 10, 20, 30, and 50, but the game compares a random integer using the > operator, and random integers start at 0, so there is an off-by-one error in the chances.)

Toadette's Music Room

Hammer Bro

Hammer Bro can warp the player to any random red or blue space.

Piano Bonus

There are 3 possible songs. Which song is given is random, with chances based on placing -- higher places get harder songs more often. The reward depends on the song played and goes down by 1 coin for every wrong note. However, if you make too many mistakes (depending on the song), you won't get any coins. Time doesn't matter as long as the song is finished within the time limit.

Song	Base Reward	Max Mistakes	1st Place	2nd Place	3rd Place	4th Place
CAGEDBC'	20	?	61%	41%	-	-
BAGDE	17	5	39%	59%	49%	29%
C'FG	15	3	-	-	51%	71%

(Like Piranha Plant, the odd percentages aren't intentional.)

DK's Stone Statue

Dry Bones

60% chance to get sent to the start, 40% chance to get sent to right before the Star Splurge Space.

Colored Vines

34% Double Dice Set, 33% Triple Dice Set, 33% Halfway Dice Block.

Kamek's Library

Jar spawning

Though there are 8 jar spaces, there are only 6 base configurations for the jars to be in:

Spoiler: Jar spaces

*The last configuration (all 3 jars in the upper loop) can't happen on the first spawn.

The game first picks one of these configurations and attempts to place the jars. If any of the chosen spaces are occupied by a player, the game runs the following steps for each jar that couldn't be placed (if multiple jars couldn't be placed, jars that are processed later can't choose spaces that were already chosen by jars processed earlier. processing order: center loop, left loop, right loop, upper loop [top left space, top right space, bottom right space]):

1. Attempt to place the jar at another jar space within the same loop. For the upper loop, it always attempts to place the jar in the top left space first, then the top right space, and lastly the bottom right space. Note that this will always fail for the jar in the center loop.
2. If step 1 fails, the jar is placed at one of the remaining spaces at random.

This only determines the locations of the 3 jars; their contents are randomly shuffled.

Kamek

A 10% chance to use Spell 88 (swaps everyone around), otherwise Spell 8 (swaps with just 1 player).

Crystal Ball

Reward	Probability
30 coins	45%
1 Star	10%
Star Pipe (if inventory is full, becomes 30 coins)	45%

Bowser's Pinball Machine

Coin Roulette

The target value is chosen randomly from 1-6, with each value having practically equal probability. The wheel can be timed with roughly a 5-frame window.

Wheel of Wonder

The wheel can be timed. The 5x wedge has roughly a 6-frame window (at 60FPS) to hit.

Pinball Plunger

The chance to go to the Star Zone depends on placing.

Placing	Chance to go to Star Zone
1st	10%
2nd	20%
3rd	25%
4th	30%

Minigames

Hedge Honcho

Of the 5 sections of hedges, 2 will have a bee, 2 will have a ladybug, and 1 will have no bug.

Trace Cadets

If a player finishes their last shape, other players can tie the minigame if they finish their last shape before the first player's shape-placing animation finishes.

Get the Lead Out

Score is 0.3 inches (centimeters outside the US) times the number of A presses. The speedometer is purely aesthetic.

Boogie Beam

Each player will have their spotlight on 5 times and off 5 times. The last go will always have all players' spotlights on. (Credit: realrider24 on YouTube)

Fast Food Frenzy

Once the solo player places an item, they must wait 40 frames (2/3 of a second) before placing the next. Each item also has an individual cooldown:

Spoiler: Item Cooldowns

Item	Cooldown (frames)	Cooldown (cycles of 40 frames)
Shake	160	4
Burger	220	5.5
Pancakes	130	3.25
Hot Dog	40	1
Fries	100	2.5
Ice Cream	40	1

Star Catchers

In board play, if multiple players fail to get any stars, they will always tie for 4th and not get any coins. Consequently, if one player claims all the stars, that player will get all the coins in the pot.

 

[Mathy]

(Reserved in case I run out of characters again)