diff --git a/neuromaps/nulls/tests/test_nulls.py b/neuromaps/nulls/tests/test_nulls.py
index fa634883..792f191f 100644
--- a/neuromaps/nulls/tests/test_nulls.py
+++ b/neuromaps/nulls/tests/test_nulls.py
@@ -2,25 +2,158 @@
 """For testing neuromaps.nulls.nulls functionality."""
 
 import pytest
+from neuromaps.datasets import fetch_annotation, available_annotations
+from neuromaps.parcellate import Parcellater
+from neuromaps.images import annot_to_gifti, dlabel_to_gifti
+from netneurotools.datasets import fetch_schaefer2018, fetch_cammoun2012
+
+sample_surface_maps = [
+    ('abagen', 'genepc1', 'fsaverage', '10k'),
+    ('hcps1200', 'myelinmap', 'fsLR', '32k'),
+]
+sample_volume_maps = [
+    ('neurosynth', 'cogpc1', 'MNI152', '2mm'),
+    ('dukart2018', 'flumazenil', 'MNI152', '3mm'),
+]
+
+sample_surface_parcellations = [
+    ("schaefer100x7", fetch_schaefer2018, '100Parcels7Networks'),
+    ("schaefer200x7", fetch_schaefer2018, '200Parcels7Networks')
+]
+
+sample_volume_parcellations = [
+    ("lausanne033", fetch_cammoun2012, 'scale033'),
+    ("lausanne060", fetch_cammoun2012, 'scale060')
+]
+
+@pytest.fixture(
+    scope="module", 
+    params=sample_surface_maps, 
+    ids=["_".join(_) for _ in sample_surface_maps]
+)
+def sample_surface(request):
+    source, desc, space, den = request.param
+    annot = fetch_annotation(
+        source=source, desc=desc, space=space, den=den
+    )
+    return request.param, annot
+
+@pytest.fixture(
+    scope="module", 
+    params=sample_volume_maps, 
+    ids=["_".join(_) for _ in sample_volume_maps]
+)
+def sample_volume(request):
+    source, desc, space, res = request.param
+    annot = fetch_annotation(
+        source=source, desc=desc, space=space, res=res
+    )
+    return request.param, annot
+
+@pytest.fixture(
+    scope="module", 
+    params=sample_surface_parcellations, 
+    ids=[_[0] for _ in sample_surface_parcellations]
+)
+def sample_surface_parcellated(sample_surface, request):
+    surf_tuple, annot = sample_surface
+    source, desc, space, den = surf_tuple
+
+    if request.param[0].startswith("schaefer"):
+        parc_name, parc_fetcher, parc_label = request.param
+        if space == "fsaverage":
+            atlas = annot_to_gifti(parc_fetcher(version="fsaverage")[parc_label])
+        elif space == "fsLR":
+            atlas = dlabel_to_gifti(parc_fetcher(version="fslr32k")[parc_label])
+        else:
+            raise NotImplementedError(f"Invalid surface space: {space}")
+        parc = Parcellater(atlas, space)
+    else:
+        raise NotImplementedError(f"Invalid parcellation: {request.param[0]}")
+
+    annot_parc = parc.fit_transform(annot, space)
+
+    return surf_tuple, parc_name, annot_parc
+
+
+@pytest.fixture(
+    scope="module", 
+    params=sample_volume_parcellations, 
+    ids=[_[0] for _ in sample_volume_parcellations]
+)
+def sample_volume_parcellated(sample_volume, request):
+    vol_tuple, annot = sample_volume
+    source, desc, space, res = vol_tuple
+
+    if request.param[0].startswith("lausanne"):
+        parc_name, parc_fetcher, parc_label = request.param
+        atlas = parc_fetcher(version="MNI152NLin2009aSym")[parc_label]
+        parc = Parcellater(atlas, space)
+    else:
+        raise NotImplementedError(f"Invalid parcellation: {request.param[0]}")
+
+    annot_parc = parc.fit_transform(annot, space)
+
+    return vol_tuple, parc_name, annot_parc
+
+
+def test_fixture_surface_smoke(sample_surface):
+    # print(sample_surface[0])
+    pass
+
+def test_fixture_volume_smoke(sample_volume):
+    # print(sample_volume[0])
+    pass
+
+# def test_fixture_surface_parcellated_smoke(sample_surface, sample_parcellation):
+#     print(sample_surface[0], sample_parcellation)
+
+# def test_fixture_volume_parcellated_smoke(sample_volume, sample_parcellation):
+#     print(sample_volume[0], sample_parcellation)
+
+
+def test_fixture_surface_parcellated_smoke(sample_surface_parcellated):
+    surf_tuple, parc_name, annot_parc = sample_surface_parcellated
+    # print(surf_tuple, parc_name, annot_parc.shape[0])
+    pass
+
+def test_fixture_volume_parcellated_smoke(sample_volume_parcellated):
+    vol_tuple, parc_name, annot_parc = sample_volume_parcellated
+    # print(vol_tuple, parc_name, annot_parc.shape[0])
+    pass
 
 
 @pytest.mark.xfail
-def test_alexander_bloch():
+def test_alexander_bloch(sample_surface):
     """Test alexander-bloch null model."""
     assert False
 
+@pytest.mark.xfail
+def test_alexander_bloch_parcellated(sample_surface, sample_parcellation):
+    """Test alexander-bloch null model for parcellated maps."""
+    assert False
+
 
 @pytest.mark.xfail
 def test_vasa():
     """Test vasa null model."""
     assert False
 
+@pytest.mark.xfail
+def test_vasa_parcellated():
+    """Test vasa null model for parcellated maps."""
+    assert False
+
 
 @pytest.mark.xfail
 def test_hungarian():
     """Test hungarian null model."""
     assert False
 
+@pytest.mark.xfail
+def test_hungarian_parcellated():
+    """Test hungarian null model for parcellated maps."""
+    assert False
 
 @pytest.mark.xfail
 def test_baum():