# The reversed, flipped and past-the-end cases of the shared animation helpers, which no object of the game
# reaches (no object sets the flags they test: see below), run by poking single fields of live objects (one player, Stage Select Mode to
# stage 4; nothing else is done, the player stands where he starts).
#
# Reaches: animate_part_list_step backwards (00E09E-00E0B3); animate_with_screen_offset backwards
# (00E015-00E026) and past its last frame (00E037); add_step_screen_offset with the sprite flipped in y
# (00E073); animate_and_move backwards (00DF1D-00DF2E), past its last frame (00DF3F) and flipped in y
# (00DF6A).
#
# Flags bit 7 (object field 30) makes these helpers step backwards; sprite_flags bit 7 (field 2) flips the
# sprite in y and negates the steps' y offsets; field 46 is the frame index (45 the countdown to the next
# step, 44 the step time). Objects and frames come from RAM dumps of this same run (it is deterministic):
# - 2600: the "how to play" hand of the game intro (stage 7, 204BA0, handler how_to_play_button_hand_update,
#   flags 0): flags = 80. Its next button presses step its part list backwards.
# - Stage 4's crumbling rock ledges (handler crumbling_floor_update) crack in turn as the ledge leader
#   passes: 4191 the ledge at 204560 (frame 3 of its 8-frame crack): countdown 1 and frame 9, so this
#   frame's step goes past the last frame; 4200 the ledge at 2044C0 (cracking, frame 1): flags = 80; 4200
#   the ledge at 204600 (holding its last frame, sprite_flags 1040): low byte C0 (flipped in y).
# - The player falls off the crumbled ledge (state 6, animate_and_move, 5-frame animation 1128D8): 4229
#   countdown 1 and frame 6 (past the last frame); 4236 flags = 80, sprite_flags low byte 8A (0A + flip),
#   countdown 1 and frame 0, so the next steps go backwards from frame 0 (the restart at 4259 resets all).
1800  press coin1
1920  press start1
2600  poke 204BD0 80
3300  poke 20F061 08
3400  poke 20F06E 04
3400  poke 20F06F 00
3500  press start1
4191  poke 2045A5 01
4191  poke 2045A6 09
4200  poke 2044F0 80
4200  poke 204602 C0
4229  poke 204FA5 01
4229  poke 204FA6 06
4236  poke 204F90 80
4236  poke 204F62 8A
4236  poke 204FA5 01
4236  poke 204FA6 00
4500  end
