diff --git a/extendeddatacrossword_test.go b/extendeddatacrossword_test.go
index 4a77363..370b36e 100644
--- a/extendeddatacrossword_test.go
+++ b/extendeddatacrossword_test.go
@@ -168,41 +168,52 @@ func TestCannotRepairSquareWithBadRoots(t *testing.T) {
 }
 
 func TestCorruptedEdsReturnsErrByzantineData(t *testing.T) {
-	bufferSize := 64
-	corruptChunk := bytes.Repeat([]byte{66}, bufferSize)
+	shareSize := 64
+	corruptChunk := bytes.Repeat([]byte{66}, shareSize)
 
 	tests := []struct {
-		name string
-		// Size of each share, in bytes
-		shareSize int
-		cells     [][]byte
-		values    [][]byte
+		name   string
+		coords [][]uint
+		values [][]byte
 	}{
-		{"BadRow/OriginalData", bufferSize, [][]byte{{0, 0}}, [][]byte{corruptChunk}},
-		{"BadRow/ExtendedData", bufferSize, [][]byte{{0, 3}}, [][]byte{corruptChunk}},
-		{"BadColumn/OriginalData", bufferSize, [][]byte{{0, 0}, {0, 1}, {0, 2}, {0, 3}}, [][]byte{corruptChunk, nil, nil, nil}},
-		{"BadColumn/OriginalData", bufferSize, [][]byte{{3, 0}, {0, 1}, {0, 2}, {0, 3}}, [][]byte{corruptChunk, nil, nil, nil}},
+		{
+			name:   "corrupt a chunk in the original data square",
+			coords: [][]uint{{0, 0}},
+			values: [][]byte{corruptChunk},
+		},
+		{
+			name:   "corrupt a chunk in the extended data square",
+			coords: [][]uint{{0, 3}},
+			values: [][]byte{corruptChunk},
+		},
+		{
+			name:   "corrupt a chunk at (0, 0) and delete shares from the rest of the row",
+			coords: [][]uint{{0, 0}, {0, 1}, {0, 2}, {0, 3}},
+			values: [][]byte{corruptChunk, nil, nil, nil},
+		},
+		{
+			name:   "corrupt a chunk at (3, 0) and delete part of the first row ",
+			coords: [][]uint{{3, 0}, {0, 1}, {0, 2}, {0, 3}},
+			values: [][]byte{corruptChunk, nil, nil, nil},
+		},
 	}
 
 	for codecName, codec := range codecs {
 		t.Run(codecName, func(t *testing.T) {
-			original := createTestEds(codec, bufferSize)
-
-			var byzData *ErrByzantineData
 			for _, test := range tests {
 				t.Run(test.name, func(t *testing.T) {
-					corrupted, err := original.deepCopy(codec)
-					if err != nil {
-						t.Fatalf("unexpected err while copying original data: %v, codec: :%s", err, codecName)
-					}
-					for i := 0; i < len(test.cells); i++ {
-						corrupted.setCell(uint(test.cells[i][0]), uint(test.cells[i][1]), test.values[i])
-					}
-					err = corrupted.Repair(corrupted.getRowRoots(), corrupted.getColRoots())
-					if !errors.As(err, &byzData) {
-						// due to parallelisation, the ErrByzantineData axis may be either row or col
-						t.Errorf("did not return a ErrByzantineData for a bad col or row; got %v", err)
+					eds := createTestEds(codec, shareSize)
+					for i, coords := range test.coords {
+						x := coords[0]
+						y := coords[1]
+						eds.setCell(x, y, test.values[i])
 					}
+					err := eds.Repair(eds.getRowRoots(), eds.getColRoots())
+					assert.Error(t, err)
+
+					// due to parallelisation, the ErrByzantineData axis may be either row or col
+					var byzData *ErrByzantineData
+					assert.ErrorAs(t, err, &byzData, "did not return a ErrByzantineData for a bad col or row")
 				})
 			}
 		})
@@ -273,11 +284,11 @@ func BenchmarkRepair(b *testing.B) {
 	}
 }
 
-func createTestEds(codec Codec, bufferSize int) *ExtendedDataSquare {
-	ones := bytes.Repeat([]byte{1}, bufferSize)
-	twos := bytes.Repeat([]byte{2}, bufferSize)
-	threes := bytes.Repeat([]byte{3}, bufferSize)
-	fours := bytes.Repeat([]byte{4}, bufferSize)
+func createTestEds(codec Codec, shareSize int) *ExtendedDataSquare {
+	ones := bytes.Repeat([]byte{1}, shareSize)
+	twos := bytes.Repeat([]byte{2}, shareSize)
+	threes := bytes.Repeat([]byte{3}, shareSize)
+	fours := bytes.Repeat([]byte{4}, shareSize)
 
 	eds, err := ComputeExtendedDataSquare([][]byte{
 		ones, twos,