IM Renier Castellanos is a Spanish chess player and coach who was born in 1982. He had a peak FIDE rating of 2528 and has 2 GM Norms.
He also holds the title of FIDE Trainer.
He has also won several tournaments in Spain and abroad.
He is also a popular online instructor who teaches chess students of various levels and ages on online platforms.
He has produced many chess courses and videos on topics such as positional chess, openings, endgames, and tactics.