Arita appeared at the Pokémon Regional Championships in Dallas, Texas, from January 26 to 28, 2018.

During the Dallas event, he held signing and commission sessions and participated in multiple talk panels.

Arita announced that his Dallas presentations would include projected examples of his artwork and demonstrations using digital media.

He produced a large mixed-media commission during the Dallas Regional Championships, measuring approximately 420 × 594 mm.

Arita attended the Pokémon World Championships in Nashville, Tennessee, in August 2018.

An official Pokémon Creator Profile documented his career and professional card-illustration process during the year.

Arita returned to Collective Con in Jacksonville, Florida, as a guest in 2018.

His growing convention activity continued to establish live drawing and direct interaction with audiences as an important part of his international career.

In 2018, Arita also appeared at Cartoomics in Milan, extending his convention activity into Europe.

Arita continued giving educational live-painting demonstrations in Japan.

A live-painting event was held at Digital Arts Tokyo in Ikebukuro on September 28, 2018.

Another documented live-painting session took place at Tohoku University of Art and Design in Yamagata on December 7, 2018.

A planned live-painting appearance at Nippon Designers School in Shibuya on July 28 was cancelled because of a typhoon.

A major 2018 interview documented Arita's professional illustration process, from receiving an assignment and preparing the composition through illustration and final approval.

Arita explained that the complete production process for a single trading-card illustration could take approximately seven weeks.

By May 2018, Arita had created 537 illustrations for the Pokémon Trading Card Game, demonstrating the scale of his professional output by this stage of his career.