diff --git a/himbaechel/uarch/ng-ultra/extra_data.h b/himbaechel/uarch/ng-ultra/extra_data.h
index 87957296..80726ef6 100644
--- a/himbaechel/uarch/ng-ultra/extra_data.h
+++ b/himbaechel/uarch/ng-ultra/extra_data.h
@@ -206,6 +206,7 @@ enum ClusterPlacement
     PLACE_FIFO_WEQ2,
     PLACE_FIFO_REQ2,
     PLACE_LUT_CHAIN,
+    PLACE_DFF_CHAIN,
 };
 
 enum PipExtra
diff --git a/himbaechel/uarch/ng-ultra/location_map.cc b/himbaechel/uarch/ng-ultra/location_map.cc
index 83123030..db709f6c 100644
--- a/himbaechel/uarch/ng-ultra/location_map.cc
+++ b/himbaechel/uarch/ng-ultra/location_map.cc
@@ -471,7 +471,7 @@ Loc getNextLocInCYChain(Loc loc)
     return result;
 }
 
-Loc getNextLocInLutChain(Loc loc)
+Loc getNextLocInLUTChain(Loc loc)
 {
     Loc result = loc;
     result.x = loc.x;
@@ -480,6 +480,24 @@ Loc getNextLocInLutChain(Loc loc)
     return result;
 }
 
+Loc getNextLocInDFFChain(Loc loc)
+{
+    Loc result = loc;
+    if (loc.z == 31) {
+        if ((loc.x & 3) == 3) {
+            result.z = -1; // End of chain
+            return result;
+        }
+        result.z = 0;
+        result.x++;
+        return result;
+    }    
+    int z = loc.z + 8;
+    if (z>31) z++;
+    result.z = z % 32; // BEL_LUT_Z is 0
+    return result;
+}
+
 Loc getCYFE(Loc root, int pos)
 {
     int p[] = { 2-1, 25-1, 10-1, 17-1 };
diff --git a/himbaechel/uarch/ng-ultra/location_map.h b/himbaechel/uarch/ng-ultra/location_map.h
index 0745d8a1..fa36b9d6 100644
--- a/himbaechel/uarch/ng-ultra/location_map.h
+++ b/himbaechel/uarch/ng-ultra/location_map.h
@@ -29,7 +29,8 @@ namespace ng_ultra {
 
 Loc getNextLocInDSPChain(const NgUltraImpl *impl, Loc loc);
 Loc getNextLocInCYChain(Loc loc);
-Loc getNextLocInLutChain(Loc loc);
+Loc getNextLocInLUTChain(Loc loc);
+Loc getNextLocInDFFChain(Loc loc);
 Loc getCYFE(Loc root, int pos);
 Loc getXLUTFE(Loc root, int pos);
 Loc getXRFFE(Loc root, int pos);
diff --git a/himbaechel/uarch/ng-ultra/ng_ultra.cc b/himbaechel/uarch/ng-ultra/ng_ultra.cc
index 643ec6d5..83666c2b 100644
--- a/himbaechel/uarch/ng-ultra/ng_ultra.cc
+++ b/himbaechel/uarch/ng-ultra/ng_ultra.cc
@@ -644,7 +644,8 @@ bool NgUltraImpl::getChildPlacement(const BaseClusterInfo *cluster, Loc root_loc
         Loc child_loc = if_using_basecluster<Loc>(child, [&](const BaseClusterInfo *child) {
             switch(child->constr_z) {
                 case PLACE_CY_CHAIN : { Loc l = getNextLocInCYChain(prev); prev = l; return l; }
-                case PLACE_LUT_CHAIN : { Loc l = getNextLocInLutChain(prev); prev = l; return l; }
+                case PLACE_LUT_CHAIN : { Loc l = getNextLocInLUTChain(prev); prev = l; return l; }
+                case PLACE_DFF_CHAIN : { Loc l = getNextLocInDFFChain(prev); prev = l; return l; }
                 case PLACE_CY_FE1 ... PLACE_CY_FE4: return getCYFE(root_loc, child->constr_z - PLACE_CY_FE1 );
                 case PLACE_XLUT_FE1 ... PLACE_XLUT_FE4: return getXLUTFE(root_loc, child->constr_z - PLACE_XLUT_FE1 );
                 case PLACE_XRF_I1 ... PLACE_XRF_WEA:
diff --git a/himbaechel/uarch/ng-ultra/pack.cc b/himbaechel/uarch/ng-ultra/pack.cc
index e53e82fa..64a74fab 100644
--- a/himbaechel/uarch/ng-ultra/pack.cc
+++ b/himbaechel/uarch/ng-ultra/pack.cc
@@ -382,6 +382,71 @@ void NgUltraPacker::pack_xluts(void)
     flush_cells();
 }
 
+void NgUltraPacker::pack_multi_dffs(void)
+{
+    log_info("Pack multi DFFs...\n");
+    std::vector<CellInfo*> dff_chain_start;
+    for (auto &cell : ctx->cells) {
+        CellInfo &ci = *cell.second;
+        if (!ci.type.in(id_NX_DFF))
+            continue;
+        NetInfo *inp = ci.getPort(id_I);
+        if (!inp || (inp->driver.cell && inp->driver.cell->type.in(id_NX_DFF))) continue;
+        int cnt = 0;
+        CellInfo *dff = &ci;
+        while(1) {
+            NetInfo *o = dff->getPort(id_O);            
+            if (o->users.entries() != 1) break;
+            dff = (*o->users.begin()).cell;
+            if (dff->type == id_NX_DFF && (*o->users.begin()).port == id_I) {
+                cnt++;
+            } else break;
+        }
+        if (cnt)
+            dff_chain_start.push_back(&ci);
+    }
+
+    int dff_only = 0, lut_and_ff = 0;
+    for (auto dff : dff_chain_start) {
+        CellInfo *root = create_cell_ptr(id_BEYOND_FE, ctx->id(dff->name.str(ctx) + "$fe"));
+        root->cluster = root->name;
+        NetInfo *net = dff->getPort(id_I);
+        NetInfo *o = dff->getPort(id_O);
+        if (net && net->driver.cell->type == id_NX_LUT && net->users.entries()==1) {
+            CellInfo *lut = net->driver.cell;
+            if (!lut->params.count(id_lut_table))
+                log_error("Cell '%s' missing lut_table\n", lut->name.c_str(ctx));
+            lut_to_fe(lut, root, false, lut->params[id_lut_table]);
+            packed_cells.insert(lut->name);
+            dff_to_fe(dff, root, false);
+            packed_cells.insert(dff->name);
+            ++lut_and_ff;
+        } else {
+            dff_to_fe(dff, root, true);
+            packed_cells.insert(dff->name);
+            ++dff_only;
+        }
+        while(1) {
+            if (o->users.entries() != 1) break;
+            dff = (*o->users.begin()).cell;
+            if (!(dff->type == id_NX_DFF && (*o->users.begin()).port == id_I)) break;
+            o = dff->getPort(id_O);
+            CellInfo *new_cell = create_cell_ptr(id_BEYOND_FE, ctx->id(dff->name.str(ctx) + "$fe"));
+            dff_to_fe(dff, new_cell, true);
+            ++dff_only;
+            root->constr_children.push_back(new_cell);
+            new_cell->cluster = root->cluster;
+            new_cell->constr_z = PLACE_DFF_CHAIN;
+            packed_cells.insert(dff->name);
+        }
+    }
+    if (lut_and_ff)
+        log_info("    %6d FEs used as LUT and DFF\n", lut_and_ff);
+    if (dff_only)
+        log_info("    %6d FEs used as DFF only\n", dff_only);
+    flush_cells();
+}
+
 void NgUltraPacker::pack_lut_multi_dffs(void)
 {
     log_info("Pack LUT-multi DFFs...\n");
@@ -1994,6 +2059,7 @@ void NgUltraImpl::pack()
     packer.pack_cys();
     packer.pack_xluts();
     packer.pack_lut_multi_dffs();
+    packer.pack_multi_dffs();
     packer.pack_lut_dffs();
     packer.pack_dffs();
 
diff --git a/himbaechel/uarch/ng-ultra/pack.h b/himbaechel/uarch/ng-ultra/pack.h
index 7be3e1b9..f8b236c3 100644
--- a/himbaechel/uarch/ng-ultra/pack.h
+++ b/himbaechel/uarch/ng-ultra/pack.h
@@ -48,6 +48,7 @@ struct NgUltraPacker
     void update_dffs();
     void pack_xluts();
     void pack_lut_multi_dffs();
+    void pack_multi_dffs();
     void pack_lut_dffs();
     void pack_dffs();
     void pack_cys();