diff --git a/maps/pirates/gui/classes.lua b/maps/pirates/gui/classes.lua
index 1a827f87..0b170a5f 100644
--- a/maps/pirates/gui/classes.lua
+++ b/maps/pirates/gui/classes.lua
@@ -7,6 +7,7 @@ local Classes = require 'maps.pirates.roles.classes'
 local GuiCommon = require 'maps.pirates.gui.common'
 local Public = {}
 
+local _inspect = require 'utils.inspect'.inspect
 
 local window_name = 'classes'
 
@@ -187,34 +188,41 @@ function Public.full_update(player, force_refresh)
 	-- Update current content table
 	for i = 1, memory.class_entry_count do
 		local label = class_list_panel_table['player_label' .. i]
-		local class_entry = memory.unlocked_classes[i]
-		label.caption = class_entry.taken_by and game.players[class_entry.taken_by].name or ''
+		if label then
+			local class_entry = memory.unlocked_classes[i]
+			label.caption = class_entry.taken_by and game.players[class_entry.taken_by].name or ''
 
-		local black = {r=0, g=0, b=0}
-		local red = {r=1, g=0, b=0}
+			local black = {r=0, g=0, b=0}
+			local red = {r=1, g=0, b=0}
 
-		local button = class_list_panel_table['button' .. i]
-		if not class_entry.taken_by then
-			button.caption = {'pirates.gui_classes_take'}
-			button.tooltip = {'pirates.gui_classes_take_enabled_tooltip'}
-			button.style.font_color = black
-			button.style.hovered_font_color = black
-			button.style.clicked_font_color = black
-			button.enabled = true
-		elseif class_entry.taken_by == player.index then
-			button.caption = {'pirates.gui_classes_drop'}
-			button.tooltip = {'pirates.gui_classes_drop_tooltip'}
-			button.style.font_color = red
-			button.style.hovered_font_color = red
-			button.style.clicked_font_color = red
-			button.enabled = true
+			local button = class_list_panel_table['button' .. i]
+			if not class_entry.taken_by then
+				button.caption = {'pirates.gui_classes_take'}
+				button.tooltip = {'pirates.gui_classes_take_enabled_tooltip'}
+				button.style.font_color = black
+				button.style.hovered_font_color = black
+				button.style.clicked_font_color = black
+				button.enabled = true
+			elseif class_entry.taken_by == player.index then
+				button.caption = {'pirates.gui_classes_drop'}
+				button.tooltip = {'pirates.gui_classes_drop_tooltip'}
+				button.style.font_color = red
+				button.style.hovered_font_color = red
+				button.style.clicked_font_color = red
+				button.enabled = true
+			else
+				button.caption = {'pirates.gui_classes_take'}
+				button.tooltip = {'pirates.gui_classes_take_disabled_tooltip'}
+				button.style.font_color = black
+				button.style.hovered_font_color = black
+				button.style.clicked_font_color = black
+				button.enabled = false
+			end
 		else
-			button.caption = {'pirates.gui_classes_take'}
-			button.tooltip = {'pirates.gui_classes_take_disabled_tooltip'}
-			button.style.font_color = black
-			button.style.hovered_font_color = black
-			button.style.clicked_font_color = black
-			button.enabled = false
+			log('Error: Non-existant label index, here some debug info.')
+			log(_inspect(class_list_panel_table))
+			log(memory.class_entry_count)
+			log(memory.unlocked_classes)
 		end
 	end
 
diff --git a/maps/pirates/surfaces/islands/cave/cave.lua b/maps/pirates/surfaces/islands/cave/cave.lua
index eff4a360..53cf0593 100644
--- a/maps/pirates/surfaces/islands/cave/cave.lua
+++ b/maps/pirates/surfaces/islands/cave/cave.lua
@@ -68,38 +68,40 @@ function Public.reveal(cave_miner, surface, source_surface, position, brushsize)
             local entity_position = entity.position
             if (position.x - entity_position.x) ^ 2 + (position.y - entity_position.y) ^ 2 < brushsize_square then
                 local e = entity.clone({position = entity_position, surface = surface})
-                if e.name == 'market' then
-                    rendering.draw_light(
-                        {
-                            sprite = 'utility/light_medium',
-                            scale = 7,
-                            intensity = 0.8,
-                            minimum_darkness = 0,
-                            oriented = true,
-                            color = {255, 255, 255},
-                            target = e,
-                            surface = surface,
-                            visible = true,
-                            only_in_alt_mode = false
-                        }
-                    )
-                end
-
-                if entity.force.index == 2 then
-                    e.active = true
-                    table.insert(cave_miner.reveal_queue, {entity.type, entity.position.x, entity.position.y})
-                end
-
-                entity.destroy()
-
-                -- make revealing a spawner recursively reveal nearby ones too
-                if e.name == 'biter-spawner' or e.name == 'spitter-spawner' then
-                    -- prevent spawners immediately spawning tons of biters for a while to give player a chance to clear them or run away
-                    if destination.dynamic_data and destination.dynamic_data.disabled_wave_timer then
-                        destination.dynamic_data.disabled_wave_timer = Balance.prevent_waves_from_spawning_in_cave_timer_length
+                if e and e.valid then
+                    if e.name == 'market' then
+                        rendering.draw_light(
+                            {
+                                sprite = 'utility/light_medium',
+                                scale = 7,
+                                intensity = 0.8,
+                                minimum_darkness = 0,
+                                oriented = true,
+                                color = {255, 255, 255},
+                                target = e,
+                                surface = surface,
+                                visible = true,
+                                only_in_alt_mode = false
+                            }
+                        )
                     end
 
-                    Public.reveal(cave_miner, surface, source_surface, entity_position, 15)
+                    if entity.force.index == 2 then
+                        e.active = true
+                        table.insert(cave_miner.reveal_queue, {entity.type, entity.position.x, entity.position.y})
+                    end
+
+                    entity.destroy()
+
+                    -- make revealing a spawner recursively reveal nearby ones too
+                    if e.name == 'biter-spawner' or e.name == 'spitter-spawner' then
+                        -- prevent spawners immediately spawning tons of biters for a while to give player a chance to clear them or run away
+                        if destination.dynamic_data and destination.dynamic_data.disabled_wave_timer then
+                            destination.dynamic_data.disabled_wave_timer = Balance.prevent_waves_from_spawning_in_cave_timer_length
+                        end
+
+                        Public.reveal(cave_miner, surface, source_surface, entity_position, 15)
+                    end
                 end
             end
         end