by Tom Buehler
Problem: Halloween Town/​Valentine’s Day Town

The entries in each half clue a celebrity, but not all are unambiguous enough to point to only one person.

The key is that each celebrity in the second half was born with a different surname than the one they are currently widely known by.

This birth name matches the current surname of a celebrity clued in the first half. The first group of clues is alphabetized by the celebrity’s commonly used first name. The second group is alphabetized by the celebrity’s first name at birth.

These are the pairings, in the order provided by the M&M photos:

Celebrity 1Celebrity 2BirthnameGreen M&MsLetter
Upton SinclairVin DieselMark Sinclair2I
George HarrisonCourtney LoveCourtney Harrison7O
Kevin McDonaldDavid TennantDavid McDonald5N
John EdwardsShania TwainEilleen Edwards1E
Jim KellyIggy AzaleaAmethyst Kelly3L
Keith HernandezBruno MarsPeter Hernandez2E
Philip LarkinJoan JettJoan Larkin5I
Tammy DuckworthKendrick LamarKendrick Duckworth8T
Tim CookAlicia KeysAlicia Cook1C
Chuck PalahniukJack PalanceVolodymyr Palahniuk5H
Jim MorrisonJohn WayneMarion Morrison6S
Shel SilversteinAndrew Dice ClayAndrew Silverstein8T
Alan GreenspanJason AlexanderJay Greenspan8A
Fred RogersPortia de RossiAmanda Rogers3G
James GarfieldHenry RollinsHenry Garfield6E
Don JohnsonWhoopi GoldbergCaryn Johnson4N
Chris PrattBoris KarloffWilliam Pratt3A
Narendra ModiKal PennKalpen Modi1M
Patty DukeSean AstinSean Duke4E

The number of blue M&Ms is the enumeration of the first name of the celebrity in the first group, while the number of yellow M&Ms is the enumeration of the birth first name of the celebrity in the second group (with the M visible when an M occurs at that position).

Indexing into the shared surname by the number of green M&Ms gives the phrase IONE LEITCH STAGE NAME.

Ione Leitch is the birth name of Ione Skye, so the answer is IONE SKYE.