Complex sentence: Thrawn himself was reintroduced into the canon in the 2016 third season of the CGI-animated television series "Star Wars Rebels" by Dave Filoni, who has used multiple characters and elements from "Legends" works in the series.
Split into simpler sentences: Thrawn himself was reintroduced into the canon by Dave Filoni in the 2016 third season of the CGI-animated television series "Star Wars Rebels". Filoni has used multiple characters and elements from "Legends" works in the series.