[2] It is Aarne-Thompson type 313A, the girl helps the hero flee and revolves about a transformation chase.
[3] Others of this type include The Master Maid, Jean, the Soldier, and Eulalie, the Devil's Daughter, The Two Kings' Children, Nix Nought Nothing, and Foundling-Bird.
[2] A brother and sister fell into a well, where a nixie caught them and made them work for her.
The girl threw a brush, which became a mountain with thousands of spikes, which the nixie got through with great effort.
The boy threw a comb behind them, which became mountains with thousands of teeth, which the nixie got through with great effort.