Robot Spirits to the Mobile Suit In Action! and In Action! Offshoot lines.
Super Robot Chogokin to Soul of Chogokin to regular Chogokin, despite both regular and Soul versions still exist.
Hero Factory temporarily substituted BIONICLE (it even said so on the packaging of the first-wave figures). BIONICLE itself was this to the earlier and short-lived Slizers and Robo Riders lines. Also, the earlier BIONICLE Rahi models were successors of the LEGO Competition playsets.
Note that fans on the other hand consider Ninjago to be it's sequel, story-wise.
The Barbie Look and the Tim Gunn Barbie dolls can count as this for the Barbie Basics line, both being collector, easy to find, fashion focused doll lines with the model muse body -more realistic and skinny- As the Basics were were oficially discontinued few months before the Gunn dolls were announced. And Word of God stated The Barbie Look was created with this intention.
Nintendo's amiibo toyline is a spiritual successor to Nintendo's ill-fated e-reader accessory for the Game Boy Advance (even more so with the amiibo cards), and because Technology Marches On, they work a lot better than the e-reader ever did.