? Card Toad
From the Super Mario Wiki, the Mario encyclopedia
? Card Toads are characters in Mario & Luigi: Paper Jam. They are Toads familiar with buying and selling ? Cards, best identifiable by each of them having purple spots as well as a ? Card icon above them. They tend to situate themselves in village shops. One Toad of a similar design and purpose informs Mario, Luigi, and Paper Mario of the arrival of both Bowsers and the kidnapping of both Princess Peaches, in addition to providing basic information about ? Cards.
As Mario, Luigi, Paper Mario, and Starlow wrap up exploration of Sunbeam Plains, a purple Toad calls out and runs toward them. He informs them of Bowser invading Peach's Castle, marking the kidnapping of Princess Peach in this game. When asked if it was just one Bowser, he replies that there were in fact two, referring of course to Paper Bowser. Just after this, a cutscene starts to confirm the intrusion and the kidnapping. The trio vow to return to the castle in time to rescue both princesses. However, barely before they are able to start doing so, both Bowsers arrive in Koopa Clown Cars, each in possession of their respective princess. They quickly advance, leaving the trio to deal with Petey Piranha.
After Petey Piranha is defeated, he drops a card Mario picks up. The purple Toad, who presumably remained in this area during the event, rushes over to inform Mario of ? Cards. He centers around the ability to turn them into character cards and how to do so via a menu tutorial, as well as the ability to exchange them for coins, being able to do so by finding Toads with a similar appearance to him and ? Card icons above their heads, usually found in village shops. He wishes them luck on their quest before heading off.
The other ? Card Toads are able to buy and sell ? Cards from Mario, Luigi, and Paper Mario. They each purchase level one cards for 200 coins each and level two cards for 800 coins. When Mario almost declares his decision, the Toad cuts him off, explaining they are a sensitive topic due to their value and best kept secret.