Presents do not have a uniform distribution; present selection is driven by a weighted random number generator. Weights are assigned as follows:
Tier 1 (Rarest):
- Promotion
- Extra Life
- Jackpot
Tier 2:
- Randomizer
- Telephone
- Extra Buck
- Tomato Rain
- Earthling
- School Book
- Boombox
Tier 3:
- Innertube
- Sling Shot
- Super Hitops
- Total Bummer
Tier 4:
- Icarus Wings
- Tomatoes
- Rocket Skates
- Rose Bushes
- Doorway
- Food
- Rootbeer
- Rain Cloud
- Fudge Sundae
- Decoy
Tier 5 (most common):
- Spring Shoes
- Unfall
- Mystery Box (question-mark present)
The value of the tier is the amount of weight it has in the RNG; in other words, whenever the game wants to choose a present, it is five times more likely that any one Tier 5 present will be selected than any one Tier 1 present.
Present selection is independent of level; any single present on Level 2 is just as likely to be a Randomizer as it is on Level 25.
Level 1 and mailboxes have special-case rules that ban certain items from appearing.
Level 1
The first four presents on level 1 (the ones in the starting area) are not allowed to be Icarus Wings, Innertube, Rocket Skates, the Mystery Box, Randomizer, or Total Bummer. When the game selects presents for those locations, if any of those six are selected, the game rerolls for something else. (This makes it so you can't get to the corner islands without first going up to Level 2.)
All other presents on Level 1 (the ones on the corner islands) are unrestricted.
Mailboxes
Mailboxes are not allowed to contain Extra Life, Promotion, nor Jackpot. (You cannot buy your way to infinite lives, infinite ranks, and infinite money!) When the game selects presents to fill the mailbox, if any of those three are selected, the game rerolls for something else.
The amount of money for each present is 3, 4, or 5 bucks, and is chosen independently of the present contents.
Mystery Boxes
The "contents" of a mystery box present are chosen either at the time of use, or the time at which they are identified (at which point they just become a regular present). Selection of the contents also uses these weights.
