Objective: How to make magnetic slime

Which of the following solutions is more sound in terms of naive physics reasoning?

OPTIONS:
a). In a bowl, pour 4 ounces of school glue. Carefully pour 1/3 cup water into the glue in the glue container and shake. add this water to the glue in the bowl. Add 2 tablespoons of magnets and 1/2 cup liquid starch to the mixture. Stir until combined and knead until stringy.;
b). in a bowl, pour 4 ounces of school glue. Carefully pour 1/3 cup water into the glue in the glue container and shake. add this water to the glue in the bowl. Add 2 tablespoons of iron oxide and 1/2 cup liquid starch to the mixture. Stir until combined and knead until stringy.;
b).