diff --git a/nc_sky_isgen/init.lua b/nc_sky_isgen/init.lua
index 51b94dd..78accfe 100644
--- a/nc_sky_isgen/init.lua
+++ b/nc_sky_isgen/init.lua
@@ -84,13 +84,24 @@ local function spawn_island(name,pos)
   ref:set_pos({x=pos.x,y=pos.y+256,z=pos.z})
 end
 local store = minetest.get_mod_storage()
+local players = minetest.deserialize(store:get_string("players")) or {}
+local cells = minetest.deserialize(store:get_string("cells")) or {}
+local function save() 
+  store:set_string("players",minetest.serialize(players))
+  store:set_string("cells",minetest.serialize(cells))
+end
 local function pid(x,z)
   return "i"..x.."_"..z
 end
 local function checkpos(x,z)
-  if store:get_string(pid(x,z)) == "" then
-    return true
+  local cell = cells[pid(x,z)]
+  local v = true
+  if cell then
+    v = cell.valid
+  else
+    v = store:get_string(pid(x,z)) == ""
   end
+  return v
 end
 minetest.override_item("ignore",{
   drawtype = "normal",
@@ -105,11 +116,32 @@ local function gen_island_pos(name)
     x,z = x+math.random(-1,1),z+math.random(-1,1)
     ok = checkpos(x,z)
   end
-  store:set_string(pid(x,z),name)
-  local range = {min={x=x*128-64,y=256-64,z=z*128-64},max={x=x*128+64,y=256+64,z=z*128+64}}
-  local ip = {x=x*128+math.random(-32,32),y=256+math.random(-32,32),z=z*128+math.random(-32,32)}
-  spawn_island(name,ip)
-  return pid(x,z),ip,range
+  local range,ip
+  local ocell = cells[pid(x,z)]
+  if ocell and ocell.valid then
+    range = ocell.islandrange
+    ip = ocell.islandpos
+    if players[ocell.name] and players[ocell.name].island == pid(x,z) then
+      players[ocell.name] = nil
+    end
+    local ref = minetest.get_player_by_name(name)
+    local pos = ip
+    pos = {x=f(pos.x),y=f(pos.y),z=f(pos.z)}
+    ref:set_pos({x=pos.x,y=pos.y+256,z=pos.z})
+  else
+    range = {min={x=x*128-64,y=256-64,z=z*128-64},max={x=x*128+64,y=256+64,z=z*128+64}}
+    ip = {x=x*128+math.random(-32,32),y=256+math.random(-32,32),z=z*128+math.random(-32,32)}
+    spawn_island(name,ip)
+  end
+  local pl = {
+    island = pid(x,z),
+    islandpos = ip,
+    islandrange = range,
+    name = name
+  }
+  players[name] = pl
+  cells[pid(x,z)] = pl
+  save()
 end
 local updrate = 0.5
 local to_upd = updrate
@@ -141,61 +173,150 @@ minetest.register_globalstep(function(dt)
   end
 end)
 
-minetest.register_chatcommand("reset",{
-  description = "Reset your island",
+local function get_standing_island(name)
+  local ref = minetest.get_player_by_name(name)
+  local pos = ref:get_pos()
+  local x = math.floor(pos.x/128+.5)
+  local z = math.floor(pos.z/128+.5)
+  return pid(x,z)
+end
+
+minetest.register_chatcommand("assign", {
+  description = "Reassign this island",
+  privs = {server = true},
   func = function(name,param)
-    local ref = minetest.get_player_by_name(name)
-    local meta = ref:get_meta()
-    local r = meta:get_string("islandrange")
-    r = minetest.deserialize(r)
-    minetest.emerge_area(r.min,r.max,function(bp,act,crem)
-      if crem > 0 then
-        return
-      end
-      local ref = minetest.get_player_by_name(name)
-      local meta = ref:get_meta()
-      local istr = meta:get_string("islandpos")
-      local pos = minetest.string_to_pos(istr)
-      if pos then
-        local r = meta:get_string("islandrange")
-        r = minetest.deserialize(r)
-        print("Resetting island "..istr.." owned by "..name)
-        air_c = minetest.get_content_id("air")
-        local vm = VoxelManip(r.min,r.max)
-        local rmi,rma = vm:get_emerged_area()
-        local var = VoxelArea:new{MinEdge=rmi,MaxEdge=rma}
-        local d = vm:get_data()
-        for x=r.min.x,r.max.x do
-          for y=r.min.y,r.max.y do
-            for z=r.min.z,r.max.z do
-              local i = var:index(x,y,z)
-              d[i] = air_c
-            end
-          end
-        end
-        local cpos = {x=(r.min.x+r.max.x)/2,y=(r.min.y+r.max.y)/2,z=(r.min.z+r.max.z)/2};
-        local r = 
-          (abs(r.min.x-cpos.x)+abs(r.max.x-cpos.x)+
-          abs(r.min.y-cpos.y)+abs(r.max.y-cpos.y)+
-          abs(r.min.z-cpos.z)+abs(r.max.z-cpos.z))/6
-        for k,v in pairs(minetest.get_objects_inside_radius(cpos,r)) do
-          v:remove()
-        end
-        vm:set_data(d)
-        vm:write_to_map()
-        spawn_island(name,pos)
-      end
-    end)
+    local is = get_standing_island(name)
+    if not minetest.get_player_by_name(param) then
+      minetest.chat_send_player(name,"No player "..param)
+      return
+    end
+    players[param] = nil
+    if not cells[is] then
+      minetest.chat_send_player(name,"No island here")
+      return
+    end
+    if not cells[is] then
+      range = {min={x=x*128-64,y=256-64,z=z*128-64},max={x=x*128+64,y=256+64,z=z*128+64}}
+      ip = {x=x*128+math.random(-32,32),y=256+math.random(-32,32),z=z*128+math.random(-32,32)}
+      spawn_island(param,ip)
+    else
+      cells[is].name = param
+    end
+    minetest.chat_send_player(name,"OK")
+    save()
+  end
+})
+
+minetest.register_chatcommand("unassign", {
+  description = "Unassign this island",
+  privs = {server = true},
+  func = function(name,param)
+    local is = get_standing_island(name)
+    if not cells[is] then
+      minetest.chat_send_player(name,"This cell is not assigned")
+      return
+    end
+    local nam = cells[is].name
+    players[nam] = nil
+    cells[is].name = ""
+    store:set_string(is,"")
+    minetest.chat_send_player(name,"OK")
+    save()
+  end
+})
+
+minetest.register_chatcommand("validate", {
+  description = "Make this island avaible for newcomers",
+  privs = {server = true},
+  func = function(name,param)
+    local is = get_standing_island(name)
+    if cells[is] then
+      cells[is].valid = true
+      minetest.chat_send_player(name,"OK")
+    else
+      minetest.chat_send_player(name,"No island here")
+      return
+    end
+    save()
+  end
+})
+
+minetest.register_chatcommand("invalidate", {
+  description = "Make this island unavaible for newcomers",
+  privs = {server = true},
+  func = function(name,param)
+    local is = get_standing_island(name)
+    if cells[is] then
+      cells[is].valid = false
+    else
+      minetest.chat_send_player(name,"No island here")
+      return
+    end
+    save()
+  end
+})
+
+minetest.register_chatcommand("query", {
+  description = "Query information about this island",
+  func = function(name,param)
+    local is = get_standing_island(name)
+    if cells[is] then
+      minetest.chat_send_player(name,is..": [")
+      minetest.chat_send_player(name,"  owner: "..((cells[is].name == "" and "(none)" or cells[is].name) or "(none)"))
+      minetest.chat_send_player(name,"  takeable: "..tostring(cells[is].valid))
+      minetest.chat_send_player(name,"  pos: "..minetest.pos_to_string(cells[is].islandpos))
+      minetest.chat_send_player(name,"  range: "..minetest.serialize(cells[is].islandrange))
+      minetest.chat_send_player(name,"]")
+    else
+      minetest.chat_send_player(name,is..": No island here")
+    end
+    save()
+  end
+})
+
+minetest.register_chatcommand("reset",{
+  description = "Get a new island",
+  privs = {interact = true},
+  func = function(name)
+    local pl = players[name]
+    if pl then
+      store:set_string(pl.island,"")
+      pl.name = nil
+      pl.valid = false
+    end
+    gen_island_pos(name)
   end
 })
 
 minetest.register_on_joinplayer(function(ref)
   local meta = ref:get_meta()
   local name = ref:get_player_name()
-  if meta:get_string("island") == "" then
-    local p,ip,r = gen_island_pos(name)
-    meta:set_string("island",p)
-    meta:set_string("islandpos",minetest.pos_to_string(ip))
-    meta:set_string("islandrange",minetest.serialize(r))
+  if meta:get_string("island") ~= "" then
+    if not cells[meta:get_string("island")] then
+      local pl = {
+        island = meta:get_string("island"),
+        islandpos = minetest.string_to_pos(meta:get_string("islandpos")),
+        islandrange = minetest.deserialize(meta:get_string("islandrange")),
+        name = name
+      }
+      players[name] = pl
+      cells[meta:get_string("island")] = pl
+    else
+      gen_island_pos(name)
+    end
+    save()
+    meta:set_string("island","")
+    meta:set_string("islandpos","")
+    meta:set_string("islandrange","")
+  else
+    if not players[name] then
+      gen_island_pos(name)
+    else
+      local p = players[name]
+      local c = cells[p.island]
+      if c.name ~= p.name then
+        gen_island_pos(name)
+      end
+    end
   end
 end)
\ No newline at end of file