The ideal move with Mathematician is to send Felis, Lightsworn Archer
(Astral is an Duelist Spirit from another world
As someone who traded Pokemon cards on the playground (where I spent most of my days) as a wee lad, the Base Set Pikachu was not regarded highly, as its artwork was not quite as clean and recognizable as Ken Sugimoris from Jungle
Serperior is also potentially good with the currently strong Venusaur ex deck, although it could take a while to evolve both Pokemon fully
The Queen, Commanding Presence A rightful ruler for your amber deck Snow Whites evil Queen makes quite the appearance in Rise of the Floodborn, with The Queen, Commanding Presence living up to its name as a formidable powerhouse on the table
Then as we cast non-creature stuff, we can make one Ally of them 1/1 size - great in a Spellslinger style shell too - note that's not just sorceries or instants too