diff --git a/src/testdir/test_blob.vim b/src/testdir/test_blob.vim
index b249bc6..ff4186a 100644
--- a/src/testdir/test_blob.vim
+++ b/src/testdir/test_blob.vim
@@ -118,6 +118,8 @@
       LET b[1 : 1] ..= 0z55
   END
   call v9.CheckLegacyAndVim9Failure(lines, ['E734:', 'E1183:', 'E734:'])
+
+  call assert_fails('let b = readblob("a1b2c3")', 'E484:')
 endfunc
 
 func Test_blob_get_range()
@@ -210,6 +212,8 @@
       call assert_true(b1 == b2)
       call assert_false(b1 is b2)
       call assert_true(b1 isnot b2)
+      call assert_true(0z != 0z10)
+      call assert_true(0z10 != 0z)
   END
   call v9.CheckLegacyAndVim9Success(lines)
 
@@ -266,7 +270,8 @@
       VAR b = 0z00
       LET b[1] = 0x11
       LET b[2] = 0x22
-      call assert_equal(0z001122, b)
+      LET b[0] = 0x33
+      call assert_equal(0z331122, b)
   END
   call v9.CheckLegacyAndVim9Success(lines)
 
@@ -281,6 +286,18 @@
       LET b[-2] = 0x33
   END
   call v9.CheckLegacyAndVim9Failure(lines, 'E979:')
+
+  let lines =<< trim END
+      VAR b = 0z00010203
+      LET b[0 : -1] = 0z33
+  END
+  call v9.CheckLegacyAndVim9Failure(lines, 'E979:')
+
+  let lines =<< trim END
+      VAR b = 0z00010203
+      LET b[3 : 4] = 0z3344
+  END
+  call v9.CheckLegacyAndVim9Failure(lines, 'E979:')
 endfunc
 
 func Test_blob_for_loop()
@@ -428,6 +445,12 @@
 
   let lines =<< trim END
       VAR b = 0zDEADBEEF
+      call remove(b, -10)
+  END
+  call v9.CheckLegacyAndVim9Failure(lines, 'E979:')
+
+  let lines =<< trim END
+      VAR b = 0zDEADBEEF
       call remove(b, 3, 2)
   END
   call v9.CheckLegacyAndVim9Failure(lines, 'E979:')