by Chris Cieslik
Answer: PLAYING CARDS
Problem: Arbor Day Town/​Pi Day Town

Each player has a set of dice—one each of a d6, d8, d10, d12, d20 and d30.

Some of the dice colors are given, others must be discovered by the solver.

Each color has an associated rule:

ColorRuleExample
RedMaximum value the die can roll.Ezequiel’s d20 = 20
YellowDie value is the position of the die in the list.Lily’s d8 = 2
GreenNone of the other dice can be lower than the green die.Tilly’s d10 = 1
BlueDie value is equal to the length of the roller’s name.Io’s d6 = 2
PurpleEqual to the average of the six dice rolled.Flint’s d10 = 4

Each player has six dice, one of each of the five colors above, plus one die that is not restricted by any rules.

These white dice correspond to letters. This is hinted at by the acrostic formed by the players’ names—LEFTOVER DICE.

Taken in the given order, they spell out the message RED MINUS BLUE:

PlayerRedYellowGreenBluePurpleWhiteLetter
Lilyd20 = 20d8 = 2d10 = 1d6 = 4d12 = 9d30 = 18R
Ezequield20 = 20d12 = 4d6 = 3d30 = 8d10 = 8d8 = 5E
Flintd6 = 6d12 = 4d8 = 1d20 = 5d10 = 4d12 = 4D
Tillyd30 = 30d6 = 1d10 = 1d8 = 5d12 = 10d20 = 13M
Orid12 = 12d20 = 5d30 = 1d6 = 3d8 = 6d10 = 9I
Viviand20 = 20d12 = 4d6 = 1d8 = 6d10 = 9d30 = 14N
Ernied12 = 12d20 = 5d6 = 2d8 = 5d10 = 9d30 = 21U
Robbyd8 = 8d30 = 6d10 = 2d6 = 5d12 = 8d20 = 19S
Dennyd6 = 6d30 = 6d12 = 1d8 = 5d10 = 4d20 = 2B
Iod20 = 20d12 = 4d8 = 2d6 = 2d10 = 8d30 = 12L
Carlied10 = 10d12 = 4d6 = 4d8 = 6d20 = 9d30 = 21U
Encarnaciond30 = 30d10 = 3d8 = 1d12 = 11d20 = 10d6 = 5E

This should direct the solver to subtract the value of the blue die from the value of the red die for each player.

Taking the letters from those spells out the answer PLAYING CARDS.

PlayerRedBlueRed - BlueLetter
Lilyd20 = 20d6 = 416P
Ezequield20 = 20d30 = 812L
Flintd6 = 6d20 = 51A
Tillyd30 = 30d8 = 525Y
Orid12 = 12d6 = 39I
Viviand20 = 20d8 = 614N
Ernied12 = 12d8 = 57G
Robbyd8 = 8d6 = 53C
Dennyd6 = 6d8 = 51A
Iod20 = 20d6 = 218R
Carlied10 = 10d8 = 64D
Encarnaciond30 = 30d12 = 1119S