Although he has not thrown an MLB pitch in 2020, Miguel Castro threw 4,341 pitches that were tracked by the PITCHf/x system between 2015 and 2019, including pitches thrown in the MLB Regular Season and Spring Training. In 2019, he relied primarily on his Sinker (98mph) and Slider (87mph), also mixing in a Change (91mph).
Basic description of 2019 pitches compared to other RHP:
His sinker is thrown at a speed that's borderline unfair, has an obvious tail, generates a high number of swings & misses compared to other pitchers' sinkers and has some natural sinking action. His slider has some two-plane movement. His change (take this with a grain of salt because he's only thrown 7 of them in 2019) is thrown extremely hard, generates an extremely high number of swings & misses compared to other pitchers' changeups, has an obvious armside fade, dives down out of the zone and results in more flyballs compared to other pitchers' changeups.