In a microwave safe bowl, melt your white chocolate chips in 30 second intervals. Stir in between and make sure its smooth. You don't want to over cook it or you will ruin the chocolate. 2 rounds should be enough.
Spread the melted white chocolate on top of the rice krispies. Using the same spoon, make sure to spread it evenly across.
Scatter the chopped Oreos evenly across the rice krispies.
In a microwave safe bowl, add your semisweet chips. Melt for 30 seconds and stir. If its not fully melted, melt for another 30 seconds.
Drizzle the semisweet chocolate on top of the rice krispies.
Scatter mini marshmallows evenly on top of the rice krispies.
Let them sit for 1 hour prior to cutting into squares and serving.