log

hg log -v -r tip:-5
hg log -r -2
hg log -p -r tip

hg log -v -p -r 4dfc32ade0ad

hg log -M -b my_branch_name -d -7

Note

-b	show changesets within the given named branch
-d	show revisions matching date spec (hg help dates)
-M	do not show merges
-p	will show you the diff for that revision number.
-r	revision number (or changeset id). Negative values e.g. -5 refer to 5 revisions into the past.
-v	verbose

For options to follow history, see the cat command…