See first video and world 4 part 1 for all details.
0:00 Mulana's Tomb: Oh hello La-Mulana reference. This level is long, and is a very mixed bag. The first two rooms seem standard enough, but then it slowly turns to testing your diligence with dodging enemies and not jumping, then guiding a super shell across a tough track. The rest of the level is more standard fare, but still challenging.
7:50 Green Switch Palace: This is still technically World 5. Just run right, jump over enemies, dodge everything and hit the Green Switch. As mentioned before, getting every Dragon Coin requires you to beat the level twice.
9:35 Oil Refinery: So this is where the oil comes from. The refinery involves a bit of many things. There's a P-Switch run, with Magikoopa showing up periodically to mess up your plans, and there's some fence climbing later on. At least the boss is really easy when compared to the rest of the level. Now, onto an even harder World 6!
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