In order to progress the story you will need to open a gate. Now this gate holds several Purple walls and a Bomb Bug.
The solution to this one is to quickly open the gate and run inside before the gate closes once again, with the gate now closed and you inside it you can proceed.
Your next task is to get the Bomb Bug and throw it towards the food so that is is eating, once it looks ready to blow up chuck the Bug towards the Purple wall to the North, this will allow you to climb to higher ground. Follow this path and it will lead to a a Fiend Transporter. Hit this Transporter towards the food and to the north so you can climb yet more Crates.
Climbing these, at the end allow yourself to drop down and you should now be on the other side of the gate once again.
From here, repeat the same process that you did for getting inside the gate and instead of throwing the Bug at the North wall throw it towards the only other purple wall instead.
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