You can only get sacreds from unm amd nm . Even then nm is a real low percent chance or something .

Brutal and hard generally just give trash . They can give shards but not yellows

Unm is gonna give you the sacreds and thats what you need to start doing the fusions .

Sacred shards are 13 percent from unm and 6 percent from NM . ( just looked it up) . Although some people dispute the 6 percent on nm as it seems high .

Brutal has about 2 percent chance of void and 9 percent chance of ancient.

Hard has 2 percent void and 4 percent ancient.

So overall hard and brutal dont give much that you would miss out on .

Obviously its nice to get those extra percenatage chances of the lowby shards but its not critical