diff --git a/mods/HUD/mcl_inventory/init.lua b/mods/HUD/mcl_inventory/init.lua
index c197bfdd96..1785ed91fc 100644
--- a/mods/HUD/mcl_inventory/init.lua
+++ b/mods/HUD/mcl_inventory/init.lua
@@ -177,7 +177,5 @@ minetest.register_on_joinplayer(function(player)
 	return_fields(player, "enchanting_lapis")
 end)
 
-if minetest.is_creative_enabled("") then
-	dofile(minetest.get_modpath(minetest.get_current_modname()).."/creative.lua")
-end
+dofile(minetest.get_modpath(minetest.get_current_modname()).."/creative.lua")
 
diff --git a/mods/HUD/mcl_inventory/mod.conf b/mods/HUD/mcl_inventory/mod.conf
index 10e6692659..1a23698b03 100644
--- a/mods/HUD/mcl_inventory/mod.conf
+++ b/mods/HUD/mcl_inventory/mod.conf
@@ -1,5 +1,5 @@
 name = mcl_inventory
 author = BlockMen
 description = Adds the player inventory and creative inventory.
-depends = mcl_init, mcl_formspec, mcl_enchanting
+depends = mcl_init, mcl_formspec, mcl_enchanting, mcl_commands
 optional_depends = mcl_armor, mcl_brewing, mcl_potions, mcl_enchanting, mcl_craftguide, mcl_player
diff --git a/mods/MISC/mcl_commands/gamemode.lua b/mods/MISC/mcl_commands/gamemode.lua
new file mode 100644
index 0000000000..bd24a76854
--- /dev/null
+++ b/mods/MISC/mcl_commands/gamemode.lua
@@ -0,0 +1,80 @@
+local S = minetest.get_translator(minetest.get_current_modname())
+
+local gamemode_ids = {
+	survival = 1,
+	creative = 2,
+}
+
+local id_to_gamemode = {}
+for gamemode, id in pairs(gamemode_ids) do
+	id_to_gamemode[id] = gamemode
+end
+
+local creative_mode = 'creative'
+
+local storage = minetest.get_mod_storage()
+
+local player_to_gamemode_id = minetest.deserialize(storage:get_string("player_to_gamemode_id") or "return {}") or {}
+minetest.register_on_shutdown(function()
+	storage:set_string("player_to_gamemode_id", minetest.serialize(player_to_gamemode_id))
+end)
+
+local core_is_creative_enabled = minetest.is_creative_enabled
+
+minetest.is_creative_enabled = function(name)
+	local id = player_to_gamemode_id[name]
+	if id then
+		local gamemode = id_to_gamemode[id]
+		if gamemode then
+			return gamemode == creative_mode
+		end
+	end
+	return core_is_creative_enabled(name)
+end
+
+local function handle_gamemode_command(player_name, new_gamemode)
+	player_to_gamemode_id[player_name] = gamemode_ids[new_gamemode]
+	return true
+end
+
+if minetest.registered_chatcommands["gamemode"] then
+	minetest.unregister_chatcommand("gamemode")
+end
+
+local function get_gamemode_param()
+	local param
+	local i = 0
+	for gamemode, _ in pairs(gamemode_ids) do
+		if i == 0 then
+			param = "("
+		else
+			param = param .. " | "
+		end
+		i = i + 1
+		param = param .. gamemode
+	end
+	if i > 0 then
+		param = param .. ") "
+	end
+	return param
+end
+
+minetest.register_chatcommand("gamemode", {
+	params = S("@1[<name>]", get_gamemode_param()),
+	description = S("Set game mode for player or yourself"),
+	privs = {server=true},
+	func = function(name, param)
+		if (param == "") then
+			return false, S("Error: No game mode specified.")
+		end
+		if (gamemode_ids[param]) then
+			handle_gamemode_command(name, param)
+		else
+			local new_gamemode, player_name = string.match(param, "^([%a]+) ([%a%d_-]+)$")
+			if not new_gamemode or not gamemode_ids[new_gamemode] or not player_name then
+				return false, S("Invalid usage, see /help @1", "gamemode")
+			end
+			handle_gamemode_command(player_name, new_gamemode)
+		end
+	end
+})
diff --git a/mods/MISC/mcl_commands/init.lua b/mods/MISC/mcl_commands/init.lua
index a287c29269..b6b07fb22b 100644
--- a/mods/MISC/mcl_commands/init.lua
+++ b/mods/MISC/mcl_commands/init.lua
@@ -1,5 +1,6 @@
 local modpath = minetest.get_modpath(minetest.get_current_modname())
 
+dofile(modpath.."/gamemode.lua")
 dofile(modpath.."/kill.lua")
 dofile(modpath.."/setblock.lua")
 dofile(modpath.."/seed.lua")
diff --git a/mods/MISC/mcl_commands/locale/mcl_commands.de.tr b/mods/MISC/mcl_commands/locale/mcl_commands.de.tr
index 68d2675179..7f21c85371 100644
--- a/mods/MISC/mcl_commands/locale/mcl_commands.de.tr
+++ b/mods/MISC/mcl_commands/locale/mcl_commands.de.tr
@@ -10,7 +10,7 @@ Kill player or yourself=Spieler oder sich selbst töten
 Can use /say=Kann „/say“ benutzen
 <message>=<Nachricht>
 Send a message to every player=Nachricht an alle Spieler senden
-Invalid usage, see /help say.=Falsche Benutzung, siehe „/help say“.
+Invalid usage, see /help @1.=Falsche Benutzung, siehe „/help @1“.
 <X>,<Y>,<Z> <NodeString>=<X>,<Y>,<Z> <Node-Bezeichner>
 Set node at given position=Node (Block) an der gegebenen Position platzieren
 Invalid node=Unültiger Node
@@ -21,3 +21,6 @@ Ban list: @1=Bannliste: @1
 Show who is logged on=Anzeigen, wer eingeloggt ist
 Displays the world seed=Den Seed der Welt anzeigen
 Only peaceful mobs allowed!=Nur friedliche Mobs erlaubt!
+@1[<name>]=
+Set game mode for player or yourself=
+Error: No game mode specified.=
diff --git a/mods/MISC/mcl_commands/locale/mcl_commands.es.tr b/mods/MISC/mcl_commands/locale/mcl_commands.es.tr
index 91b21eb91c..a04d4aaf13 100644
--- a/mods/MISC/mcl_commands/locale/mcl_commands.es.tr
+++ b/mods/MISC/mcl_commands/locale/mcl_commands.es.tr
@@ -21,3 +21,6 @@ Ban list: @1=Lista de baneados: @1
 Show who is logged on=Mostrar quién ha iniciado sesión
 Displays the world seed=Muestra la semilla del mundo
 Only peaceful mobs allowed!=¡Solo se permiten animales pacíficos!
+@1[<name>]=
+Set game mode for player or yourself=
+Error: No game mode specified.=
diff --git a/mods/MISC/mcl_commands/locale/mcl_commands.fr.tr b/mods/MISC/mcl_commands/locale/mcl_commands.fr.tr
index a655368bf4..e83913264c 100644
--- a/mods/MISC/mcl_commands/locale/mcl_commands.fr.tr
+++ b/mods/MISC/mcl_commands/locale/mcl_commands.fr.tr
@@ -10,7 +10,7 @@ Kill player or yourself=Tuez un joueur ou vous-même
 Can use /say=Peut utiliser /say
 <message>=<message>
 Send a message to every player=Envoyez un message à chaque joueur
-Invalid usage, see /help say.=Utilisation non valide, voir /help say.
+Invalid usage, see /help @1.=Utilisation non valide, voir /help @1.
 <X>,<Y>,<Z> <NodeString>=<X>,<Y>,<Z> <NodeString>
 Set node at given position=Placer le noeud à une position donnée
 Invalid node=Noeud non valide
@@ -21,3 +21,6 @@ Ban list: @1=Liste d'interdiction: @1
 Show who is logged on=Afficher qui est connecté
 Displays the world seed=Affiche la graine du monde
 Only peaceful mobs allowed!=Seuls les mobs pacifiques sont autorisées!
+@1[<name>]=
+Set game mode for player or yourself=
+Error: No game mode specified.=
diff --git a/mods/MISC/mcl_commands/locale/mcl_commands.pl.tr b/mods/MISC/mcl_commands/locale/mcl_commands.pl.tr
index 4a3ad181cf..bacdae3a98 100644
--- a/mods/MISC/mcl_commands/locale/mcl_commands.pl.tr
+++ b/mods/MISC/mcl_commands/locale/mcl_commands.pl.tr
@@ -10,7 +10,7 @@ Kill player or yourself=Zabij gracza lub siebie
 Can use /say=Może używać /say
 <message>=<wiadomość>
 Send a message to every player=Wyślij wiadomość do każdego gracza
-Invalid usage, see /help say.=Niepoprawne użyciu, zobacz /help say.
+Invalid usage, see /help @1.=Niepoprawne użyciu, zobacz /help @1.
 <X>,<Y>,<Z> <NodeString>=<X>,<Y>,<Z> <ID Node'a>
 Set node at given position=Ustaw node w danej pozycji
 Invalid node=Niepoprawny node
@@ -21,3 +21,6 @@ Ban list: @1=Lista zbanowanych: @1
 Show who is logged on=Pokaż zalogowanych
 Displays the world seed=Wyświetl ziarno świata
 Only peaceful mobs allowed!=Tylko pokojowe moby dozwolone!
+@1[<name>]=
+Set game mode for player or yourself=
+Error: No game mode specified.=
diff --git a/mods/MISC/mcl_commands/locale/mcl_commands.ru.tr b/mods/MISC/mcl_commands/locale/mcl_commands.ru.tr
index 686c8067c0..4378e5de5a 100644
--- a/mods/MISC/mcl_commands/locale/mcl_commands.ru.tr
+++ b/mods/MISC/mcl_commands/locale/mcl_commands.ru.tr
@@ -10,7 +10,7 @@ Kill player or yourself=Убить игрока или себя
 Can use /say=Можно использовать /say
 <message>=<сообщение>
 Send a message to every player=Отправляет сообщение всем игрокам
-Invalid usage, see /help say.=Недопустимое использование, см. /help say.
+Invalid usage, see /help @1.=Недопустимое использование, см. /help @1.
 <X>,<Y>,<Z> <NodeString>=<X>,<Y>,<Z> <СтрокаУзла>
 Set node at given position=Устанавливает узел в заданной позиции
 Invalid node=Неправильный узел
@@ -21,3 +21,6 @@ Ban list: @1=Бан-лист: @1
 Show who is logged on=Показывает, кто подключён
 Displays the world seed=Показывает значение зерна мира (seed)
 Only peaceful mobs allowed!=Включены только мирные мобы!
+@1[<name>]=@1[<имя>]
+Set game mode for player or yourself=Задаёт режим игры для игрока или для вас
+Error: No game mode specified.=Ошибка: Режим игры не указан.
diff --git a/mods/MISC/mcl_commands/locale/template.txt b/mods/MISC/mcl_commands/locale/template.txt
index 5b4370b8fb..b42f06085e 100644
--- a/mods/MISC/mcl_commands/locale/template.txt
+++ b/mods/MISC/mcl_commands/locale/template.txt
@@ -10,7 +10,7 @@ Kill player or yourself=
 Can use /say=
 <message>=
 Send a message to every player=
-Invalid usage, see /help say.=
+Invalid usage, see /help @1.=
 <X>,<Y>,<Z> <NodeString>=
 Set node at given position=
 Invalid node=
@@ -21,3 +21,6 @@ Ban list: @1=
 Show who is logged on=
 Displays the world seed=
 Only peaceful mobs allowed!=
+@1[<name>]=
+Set game mode for player or yourself=
+Error: No game mode specified.=
diff --git a/mods/MISC/mcl_commands/say.lua b/mods/MISC/mcl_commands/say.lua
index 9fd53c174e..5f5bc5b009 100644
--- a/mods/MISC/mcl_commands/say.lua
+++ b/mods/MISC/mcl_commands/say.lua
@@ -10,7 +10,7 @@ minetest.register_chatcommand("say", {
 	privs = {announce=true},
 	func = function(name, param)
 		if not param then
-			return false, S("Invalid usage, see /help say.")
+			return false, S("Invalid usage, see /help @1.", "say")
 		end
 		minetest.chat_send_all(("["..name.."] "..param))
 		return true
diff --git a/mods/PLAYER/mcl_anticheat/init.lua b/mods/PLAYER/mcl_anticheat/init.lua
new file mode 100644
index 0000000000..25ec3fd485
--- /dev/null
+++ b/mods/PLAYER/mcl_anticheat/init.lua
@@ -0,0 +1,173 @@
+local flights_kick_threshold = 10
+local suffocations_kick_threshold = 1
+
+local after                     = minetest.after
+local get_connected_players     = minetest.get_connected_players
+local get_node                  = minetest.get_node
+local get_objects_inside_radius = minetest.get_objects_inside_radius
+local get_player_by_name        = minetest.get_player_by_name
+local kick_player               = minetest.kick_player
+local set_node                  = minetest.set_node
+
+local ceil  = math.ceil
+local floor = math.floor
+
+local distance = vector.distance
+
+local window_size = 10
+local detection_interval = 1.7
+local step_seconds = detection_interval / window_size
+local joined_players = {}
+
+local function update_player(player_object)
+	if not player_object then return end
+	local name = player_object:get_player_name()
+	if not name then return end
+
+	local pos = player_object:get_pos()
+	local x, y, z = floor(pos.x), floor(pos.y-0.1), floor(pos.z)
+
+	if mcl_playerplus.elytra then
+		local elytra = mcl_playerplus.elytra[player_object]
+		if elytra and elytra.active then
+			return
+		end
+	end
+
+	local air = get_node({x = x    , y = y    , z = z    }).name == "air"
+		and get_node({x = x    , y = y    , z = z + 1}).name == "air"
+		and get_node({x = x    , y = y + 1, z = z    }).name == "air"
+		and get_node({x = x    , y = y + 1, z = z + 1}).name == "air"
+		and get_node({x = x + 1, y = y    , z = z    }).name == "air"
+		and get_node({x = x + 1, y = y    , z = z + 1}).name == "air"
+		and get_node({x = x + 1, y = y + 1, z = z    }).name == "air"
+		and get_node({x = x + 1, y = y + 1, z = z + 1}).name == "air"
+
+	local player_data = {
+		pos = pos,
+		velocity = player_object:get_velocity(),
+		air = air
+	}
+
+	if joined_players[name] then
+		local window_offset = (joined_players[name].window_offset + 1) % window_size
+		joined_players[name].window_offset = window_offset
+		joined_players[name][window_offset] = player_data
+	else
+		joined_players[name] = {
+			window_offset = 0,
+			[0] = player_data,
+		}
+	end
+end
+
+local function check_player(name)
+	if minetest.is_creative_enabled(name) then return end
+	local data = joined_players[name]
+	if not data then return end
+	if not data[0] then return end
+
+	local always_air = true
+	local falling = data[0].velocity.y < 0
+	for i = 0, window_size - 1 do
+		local derivative = data[i]
+		local not_enough_data = not derivative
+		if not_enough_data then
+			return
+		end
+		always_air = always_air and derivative.air
+		falling = falling or derivative.velocity.y < 0
+	end
+	if always_air and not falling then
+		-- fly detected
+		if not data.flights then
+			data.flights = 1
+		else
+			data.flights = data.flights + 1
+			if data.flights >= flights_kick_threshold then
+				kick_player(name, "flights")
+			end
+		end
+		local obj_player = minetest.get_player_by_name(name)
+		if not obj_player then
+			kick_player(name, "flights")
+		end
+		local velocity = obj_player:get_velocity()
+		local pos = obj_player:get_pos()
+		local x, y, z = floor(pos.x), floor(pos.y), floor(pos.z)
+		while (     get_node({x = x    , y = y, z = z    }).name == "air"
+			and get_node({x = x    , y = y, z = z + 1}).name == "air"
+			and get_node({x = x + 1, y = y, z = z    }).name == "air"
+			and get_node({x = x + 1, y = y, z = z + 1}).name == "air"
+		) do
+			y = y - 1
+		end
+		obj_player:set_velocity({x = velocity.x, y = -10, z = velocity.z})
+		obj_player:set_pos({x = x, y = y + 0.5, z = z})
+	end
+end
+
+local function remove_player(player_object)
+	if not player_object then return end
+	local name = player_object:get_player_name()
+	if not name then return end
+	minetest.after(step_seconds, function()
+		joined_players[name] = nil
+	end)
+end
+
+local function step()
+	for _, player in pairs(get_connected_players()) do
+		update_player(player)
+		check_player(player:get_player_name())
+	end
+	after(step_seconds, step)
+end
+
+minetest.register_on_placenode(function(pos, newnode, placer, oldnode, itemstack, pointed_thing)
+	if not oldnode then return end
+	if not placer then return end
+	if oldnode.name ~= "air" then return end
+	if not placer:is_player() then return end
+	local placer_pos = placer:get_pos()
+	local placer_distance = distance(pos, placer_pos)
+	if placer_distance < 13 then return end
+	local is_choker = false
+	for _, object in pairs(get_objects_inside_radius(pos, 2)) do
+		if object and object:is_player() then
+			local player_head_pos = object:get_pos()
+			player_head_pos.y = player_head_pos.y + 1.5
+			local player_head_distance = distance(pos, player_head_pos)
+			if player_head_distance < 0.7 then
+				after(0.05, function(node)
+					set_node(pos, node)
+				end, oldnode)
+				is_choker = true
+				break
+			end
+		end
+	end
+	if not is_choker then return end
+	-- cheater choked the player from distance greater than 12:
+	local name = placer:get_player_name()
+	local data = joined_players[name]
+	if not data then
+		joined_players[name].suffocations = 1
+		data = joined_players[name]
+	else
+		if not data.suffocations then
+			data.suffocations = 1
+		else
+			data.suffocations = data.suffocations + 1
+		end
+	end
+	if data.suffocations >= suffocations_kick_threshold then
+		kick_player(name, "choker")
+	end
+end)
+
+minetest.register_on_joinplayer(update_player)
+
+minetest.register_on_leaveplayer(remove_player)
+
+after(step_seconds, step)