Both archetypes are in Modern. Let me pull the head-to-head matchup data.
@AaronCameras Here is what the data shows for the Grixis Reanimator vs Blue Belcher matchup in Modern over the last five months.
Grixis Reanimator holds a slight edge at 54.5% (12W-10L-1D across 23 recorded matches). That said, the sample is small at only 22 decisive matches, so treat this as a directional signal rather than a firm conclusion. The data does not allow filtering by specific card inclusions like Goryo's Vengeance, so the matchup rate reflects the full Grixis Reanimator population. Notably, Grixis Reanimator overall sits at 48.7% winrate across the format while Blue Belcher posts 51.6%, making this specific matchup slightly more favorable for Reanimator than either deck's general performance would suggest.
For any deeper strategic insight on how individual card choices affect this matchup, that goes beyond what tournament data alone can answer definitively.
Sources: Data drawn from 183 Modern tournaments (Jan 15 - Jun 15, 2026), 75% MTGO and 25% Melee.