has released a free pack of 24 environment sculpting brushes (including rocks, mud, and vegetation) on his Gumroad store.
Many professional artists offer "sample" packs or "pay-what-you-want" brushes. nomad sculpt brushes free download
Your Ultimate Guide to Free Nomad Sculpt Brushes: Best Sources and Setup has released a free pack of 24 environment
These files contain pre-configured settings (like pressure and falloff) along with their icons. Nomad Sculpt - Import Tools - Brushes nomad sculpt brushes free download