diff --git a/data/lua/core.lua b/data/lua/core.lua
index 92259ebda216..9d1331cda25c 100644
--- a/data/lua/core.lua
+++ b/data/lua/core.lua
@@ -593,6 +593,24 @@ if wesnoth.kernel_type() == "Game Lua Kernel" then
 	wesnoth.theme_items = wesnoth.deprecate_api('wesnoth.theme_items', 'wesnoth.interface.game_display', 1, nil, wesnoth.interface.game_display)
 	wesnoth.get_displayed_unit = wesnoth.deprecate_api('wesnoth.get_displayed_unit', 'wesnoth.interface.get_displayed_unit', 1, nil, wesnoth.interface.get_displayed_unit)
 	wesnoth.gamestate_inspector = wesnoth.deprecate_api('wesnoth.gamestate_inspector', 'gui.show_inspector', 1, nil, gui.show_inspector)
+	-- Units module
+	wesnoth.match_unit = wesnoth.deprecate_api('wesnoth.match_unit', 'wesnoth.units.matches', 1, nil, wesnoth.units.matches)
+	wesnoth.put_recall_unit = wesnoth.deprecate_api('wesnoth.put_recall_unit', 'wesnoth.units.to_recall', 1, nil, wesnoth.units.to_recall)
+	wesnoth.put_unit = wesnoth.deprecate_api('wesnoth.put_unit', 'wesnoth.units.to_map', 1, nil, wesnoth.units.to_map)
+	wesnoth.erase_unit = wesnoth.deprecate_api('wesnoth.erase_unit', 'wesnoth.units.erase', 1, nil, wesnoth.units.erase)
+	wesnoth.copy_unit = wesnoth.deprecate_api('wesnoth.copy_unit', 'wesnoth.units.clone', 1, nil, wesnoth.units.clone)
+	wesnoth.extract_unit = wesnoth.deprecate_api('wesnoth.extract_unit', 'wesnoth.units.extract', 1, nil, wesnoth.units.extract)
+	wesnoth.advance_unit = wesnoth.deprecate_api('wesnoth.advance_unit', 'wesnoth.units.advance', 1, nil, wesnoth.units.advance)
+	wesnoth.add_modification = wesnoth.deprecate_api('wesnoth.add_modification', 'wesnoth.units.add_modification', 1, nil, wesnoth.units.add_modification)
+	wesnoth.remove_modifications = wesnoth.deprecate_api('wesnoth.remove_modifications', 'wesnoth.units.remove_modifications', 1, nil, wesnoth.units.remove_modifications)
+	wesnoth.unit_resistance = wesnoth.deprecate_api('wesnoth.unit_resistance', 'wesnoth.units.resistance', 1, nil, wesnoth.units.resistance)
+	wesnoth.unit_defense = wesnoth.deprecate_api('wesnoth.unit_defense', 'wesnoth.units.defense', 1, nil, wesnoth.units.defense)
+	wesnoth.unit_movement_cost = wesnoth.deprecate_api('wesnoth.unit_movement_cost', 'wesnoth.units.movement', 1, nil, wesnoth.units.movement)
+	wesnoth.unit_vision_cost = wesnoth.deprecate_api('wesnoth.unit_vision_cost', 'wesnoth.units.vision', 1, nil, wesnoth.units.vision)
+	wesnoth.unit_jamming_cost = wesnoth.deprecate_api('wesnoth.unit_jamming_cost', 'wesnoth.units.jamming', 1, nil, wesnoth.units.jamming)
+	wesnoth.unit_ability = wesnoth.deprecate_api('wesnoth.unit_ability', 'wesnoth.units.ability', 1, nil, wesnoth.units.ability)
+	wesnoth.transform_unit = wesnoth.deprecate_api('wesnoth.transform_unit', 'wesnoth.units.transform', 1, nil, wesnoth.units.transform)
+	wesnoth.select_unit = wesnoth.deprecate_api('wesnoth.select_unit', 'wesnoth.units.select', 1, nil, wesnoth.units.select)
 end
 wesnoth.tovconfig = wesnoth.deprecate_api('wesnoth.tovconfig', 'wml.tovconfig', 1, nil, wesnoth.tovconfig)
 wesnoth.debug = wesnoth.deprecate_api('wesnoth.debug', 'wml.tostring', 1, nil, wesnoth.debug)
diff --git a/data/lua/helper.lua b/data/lua/helper.lua
index 5eb426d26c6a..da6a2be2c448 100644
--- a/data/lua/helper.lua
+++ b/data/lua/helper.lua
@@ -35,13 +35,6 @@ function helper.all_teams()
 	return f, { i = 1 }
 end
 
---! Modifies all the units satisfying the given @a filter.
---! @param vars key/value pairs that need changing.
---! @note Usable only during WML actions.
-function helper.modify_unit(filter, vars)
-	wesnoth.units.modify(filter, vars)
-end
-
 -- Metatable that redirects access to wml.variables_proxy
 local proxy_var_mt = {
 	__metatable = "WML variables",
@@ -250,5 +243,6 @@ helper.set_wml_var_metatable = wesnoth.deprecate_api('helper.set_wml_var_metatab
 helper.set_wml_tag_metatable = wesnoth.deprecate_api('helper.set_wml_tag_metatable', 'wml.tag', 2, nil, helper.set_wml_tag_metatable)
 helper.move_unit_fake = wesnoth.deprecate_api('helper.move_unit_fake', 'wesnoth.interface.move_unit_fake', 1, nil, wesnoth.interface.move_unit_fake)
 helper.get_user_choice = wesnoth.deprecate_api('helper.get_user_choice', 'gui.get_user_choice', 1, nil, gui.get_user_choice)
+helper.modify_unit = wesnoth.deprecate_api('helper.modify_unit', 'wesnoth.units.modify', 1, nil, wesnoth.units.modify)
 
 return helper