This is a playthrough of Sonic and the Secret Rings for the Nintendo Wii (timestamps + mandatory level list below).

This video covers the mandatory missions necessary to initially unlock the standard ending of the game, then unlock the true final boss. Sonic and the Secret Rings has an unusual and often unclear level progression structure, so if you're unsure which missions you need to play to beat the game the list below may help.

0:00:00 Opening

Lost Prologue:
0:07:20 Paragraph 01
0:08:19 Paragraph 02
0:09:19 Paragraph 03
0:10:31 Paragraph 04
0:11:42 Paragraph 05
0:12:38 Paragraph 06
0:13:16 Paragraph 07
0:14:03 Paragraph 08

Sand Oasis:
0:18:20 Go for the Goal Find King Shahryar!
0:25:06 Diehard Challenge Don't Get Defeated!
0:26:37 Special Challenge Don't Break the Jar!
0:29:58 Special Challenge Break 5 Jars!

Dinosaur Jungle:
0:31:38 Go for the Goal Follow the Pterosaur!
0:37:23 Diehard Challenge Don't Get Defeated!
0:40:14 Rampage Defeat 10 Enemies!
0:43:34 Stealth Attack Don't Defeat Enemies!

Evil Foundry:
0:45:18 Go for the Goal Head for the Centre!

Sand Oasis:
0:54:11 Head to Head Beat Uhu to the Goal!

Levitated Ruin:
0:56:48 Go for the Goal Find Sinbad!
1:06:26 Special Challenge Open Sinbad's Cage!

Pirate Storm:
1:14:58 Go for the Goal Follow the Pirates!
1:22:57 Diehard Challenge Don't Get Defeated!
1:25:06 Stealth Attack Don't Defeat Enemies!
1:27:37 Rampage Defeat 20 Enemies!
1:32:18 Defeat the boss Battle! Captain Bemoth!

Evil Foundry:
1:37:55 Diehard Challenge Don't Get Defeated!
1:40:19 Defeat the boss Battle! Ifrit Golem!
1:45:53 Beat the Clock Find the Exit in Time!

Skeleton Dome:
1:50:34 Go for the Goal Find King Solomon!
1:58:50 Rampage! Defeat 40 Enemies!
2:04:22 Special Challenge Find the King's Bones!
2:10:30 Rampage Defeat 15 Enemies!

Night Palace:
2:16:18 Go for the Goal Sneak Into the Palace!
2:24:19 Boss Duel Erazor Djinn!

2:29:16 Credits Standard Medley (The Palace That Was Found/The White of Sky/Let the Speed Mend It)

Sand Oasis:
2:36:46 Collect Rings Collect 99 Rings!
2:38:13 Diehard Challenge Don't Get Defeated!
2:40:09 Beat the Clock Finish Within 120 seconds!
2:43:06 Defeat the boss Battle! Sand Scorpion

Dinosaur Jungle:
2:46:29 Special Challenge Smash 5 Genie Eggs!

Levitated Ruin:
2:50:48 Diehard Challenge Don't Get Defeated!
2:52:11 Rampage! Defeat 1 Enemy!
2:52:57 Rampage! Defeat 20 Enemies!

Night Palace:
2:58:10 Head to Head Beat Uhu to the Goal!
2:59:54 Diehard Challenge Don't Get Defeated!
3:04:59 Hands Off Finish with 0 Rings!
3:06:44 Rampage Defeat 20 Enemies!
3:11:24 Last Chapter

3:23:04 Credits Worth a Chance/Let the Speed Mend It