Rinse sushi rice under cold water until clear, then combine with water and konbu in rice cooker. Cook for about 30 minutes.

Heat rice vinegar, sugar, and salt in a saucepan until dissolved (3-5 minutes). Let cool.

Slice toppings and cut nori sheets into fun shapes using scissors.

Transfer cooled rice to a bowl, drizzle with sushi vinegar, and fold in gently until coated.

Form sushi balls by pressing a small amount of rice and a topping into plastic wrap.

Decorate with nori shapes using tweezers for each sushi ball.

Serve on a platter with soy sauce, mayonnaise, wasabi, and pickled ginger.