FATAL: unknown option 'h'

[ScratchRZL]

rgbgfx -h -o gfx/pokedex/question_mark.2bpp gfx/pokedex/question_mark.png
FATAL: unknown option 'h'
Usage: rgbgfx [-r stride] [-CmOuVZ] [-v [-v ...]] [-a <attr_map> | -A]
[-b <base_ids>] [-c ] [-d ] [-L ] [-N <nb_tiles>]
[-n <nb_pals>] [-o <out_file>] [-p <pal_file> | -P] [-q <pal_map> | -Q]
[-s <nb_colors>] [-t <tile_map> | -T] [-x <nb_tiles>]
Useful options:
-m, --mirror-tiles optimize out mirrored tiles
-o, --output output the tile data to this path
-t, --tilemap output the tile map to this path
-u, --unique-tiles optimize out identical tiles
-V, --version print RGBGFX version and exit

For help, use `man rgbgfx' or go to https://rgbds.gbdev.io/docs/
make: *** [Makefile:220: gfx/pokedex/question_mark.2bpp] Error 1

[Rangi42]

Use INSTALL.md's instructed version of RGBDS.