Challenge Mode

Challenge Mode

Video tutorial by Undead

Challenge Mode is a special feature added in Peer Review DLC, allowing the player to compete with their friends in the lowest completion time and the least amount of placed portals.

Least Portals

See Least Portals for more information.

Unlocking Non-CM Levels

There are 11 levels existing in singleplayer campaign that are not available in Challenge Mode. However, it is possible to get them with simple game file modification. Here's step-by-step tutorial:

1. Open the game's directory (it's C:/Program Files (x86)/Steam/steamapps/common/Portal 2 by default).
2. Go to portal2_dlc1 folder and open the challenge_maplist.txt file.
3. Replace all of its context with the text below:

"challenge_maps"{"sp"{"chapter_1"{"map""sp_a1_intro1""map""sp_a1_intro2""map""sp_a1_intro3""map""sp_a1_intro4""map""sp_a1_intro5""map""sp_a1_intro6""map""sp_a1_intro7""map""sp_a1_wakeup""map""sp_a2_intro"}"chapter_2"{"map""sp_a2_laser_intro""map""sp_a2_laser_stairs""map""sp_a2_dual_lasers""map""sp_a2_laser_over_goo""map""sp_a2_catapult_intro""map""sp_a2_trust_fling""map""sp_a2_pit_flings""map""sp_a2_fizzler_intro"}"chapter_3"{"map""sp_a2_sphere_peek""map""sp_a2_ricochet""map""sp_a2_bridge_intro""map""sp_a2_bridge_the_gap""map""sp_a2_turret_intro""map""sp_a2_laser_relays""map""sp_a2_turret_blocker""map""sp_a2_laser_vs_turret""map""sp_a2_pull_the_rug"}"chapter_4"{"map""sp_a2_column_blocker""map""sp_a2_laser_chaining""map""sp_a2_triple_laser""map""sp_a2_bts1""map""sp_a2_bts2"}"chapter_5"{"map""sp_a2_bts3""map""sp_a2_bts4""map""sp_a2_bts5""map""sp_a2_bts6""map""sp_a2_core"}"chapter_6"{"map""sp_a3_00""map""sp_a3_01""map""sp_a3_03""map""sp_a3_jump_intro""map""sp_a3_bomb_flings""map""sp_a3_crazy_box""map""sp_a3_transition01"}"chapter_7"{"map""sp_a3_speed_ramp""map""sp_a3_speed_flings""map""sp_a3_portal_intro""map""sp_a3_end"}"chapter_8"{"map""sp_a4_intro""map""sp_a4_tb_intro""map""sp_a4_tb_trust_drop""map""sp_a4_tb_wall_button""map""sp_a4_tb_polarity""map""sp_a4_tb_catch""map""sp_a4_stop_the_box""map""sp_a4_laser_catapult""map""sp_a4_laser_platform""map""sp_a4_speed_tb_catch""map""sp_a4_jump_polarity"}"chapter_9"{"map""sp_a4_finale1""map""sp_a4_finale2""map""sp_a4_finale3""map""sp_a4_finale4"}}"coop"{"chapter_1"{"map""mp_coop_doors""map""mp_coop_race_2""map""mp_coop_laser_2""map""mp_coop_rat_maze""map""mp_coop_laser_crusher""map""mp_coop_teambts"}"chapter_2"{"map""mp_coop_fling_3""map""mp_coop_infinifling_train""map""mp_coop_come_along""map""mp_coop_fling_1""map""mp_coop_catapult_1""map""mp_coop_multifling_1""map""mp_coop_fling_crushers""map""mp_coop_fan"}"chapter_3"{"map""mp_coop_wall_intro""map""mp_coop_wall_2""map""mp_coop_catapult_wall_intro""map""mp_coop_wall_block""map""mp_coop_catapult_2""map""mp_coop_turret_walls""map""mp_coop_turret_ball""map""mp_coop_wall_5"}"chapter_4"{"map""mp_coop_tbeam_redirect""map""mp_coop_tbeam_drill""map""mp_coop_tbeam_catch_grind_1""map""mp_coop_tbeam_laser_1""map""mp_coop_tbeam_polarity""map""mp_coop_tbeam_polarity2""map""mp_coop_tbeam_polarity3""map""mp_coop_tbeam_maze""map""mp_coop_tbeam_end"}"chapter_5"{"map""mp_coop_paint_come_along""map""mp_coop_paint_redirect""map""mp_coop_paint_bridge""map""mp_coop_paint_walljumps""map""mp_coop_paint_speed_fling""map""mp_coop_paint_red_racer""map""mp_coop_paint_speed_catch""map""mp_coop_paint_longjump_intro"}"chapter_6"{"map""mp_coop_separation_1""map""mp_coop_tripleaxis""map""mp_coop_catapult_catch""map""mp_coop_2paints_1bridge""map""mp_coop_paint_conversion""map""mp_coop_bridge_catch""map""mp_coop_laser_tbeam""map""mp_coop_paint_rat_maze""map""mp_coop_paint_crazy_box"}}}

1. After saving and restarting the game you should have access to missing levels.

Keep in mind that scores from these levels are not updated automatically on iVerb's CM leaderboard. Because of that, you have to submit scores manually. In-game leaderboard, however, still works fine.