A little help with appearing layers?

[DakotaSpine]

I just need to know how to make layers appear without having to disappear in the first place. For example.

I want the player to have to beat a boss so a platform can appear. But the problem is, the layer is still there even when I set it to appear after the boss is defeated. I tried it the other way around, to have them disappear when a boss is beaten, and that worked. So, can anybody help me?

[FanofSMBX]

Uncheck the box on the layers menu beside the layer.

[DakotaSpine]

Uncheck the box on the layers menu beside the layer.

Ah! Alright. Thank you... I feel stupid for not getting that now XD