Snakes and Ladders
First the flag is split between two strings - one with every second byte and one with all the others.
After the encryption the strings are concatenated. First encryption: it boils down to rot-14. Second encryption: xor with 'a'
.
rcfnvrgn4gv_0_p
at{33_0n_13yuu}
Flag: ractf{n3v3r_g0nn4_g1v3_y0u_up}