It would be nice if we could define a max y level when doing things like diamond ore break lookups on busy servers so we can attempt to filter out those players that obtain the ore using silk touch in order to use fortune on them when they return to their base.

I would like to negate the x and z cords how would I apply that to a global lookup with a "only check below y40"
/co l b:deepslate_diamond_ore,diamond_ore t:2d a:-block r:global

You can already use r:0x0x0 (x/y/z)

You can also specify a location with c:0,0,0.

E.g. if you’re at x50/z244, you should be able to do something like this for a radius lookup on lower y levels:

co l c:50,0,244 r:50x10x50

I don't see a way to specify a max y level on a global lookup so I feel my Feature Request is a valid one and not a question unless I'm missing something? Granted I could have probably worded my initial comment better.

"Global" radiuses are unsupported, as the query overwhelms large databases.

You can use my example command and specify a large x/z range.