pretty nice minimalist pack, not so sure about the colours and also some of the shapes are not very distinctive, like the spikes. Overall, I'd work on this more - maybe try finding a colour palette?
Ah yes I have gotten the same suggestion for spikes and i will improve it. About the pallet there is actually no the pallet the only thing I kept in mind while making this was that each 8x8 tile can't have more than 2 colours. Thanks for the suggestion.