#Pyth - 3 bytes

Very simple, will add expansion later, on mobile.

s.T

Test Suite

s                         Join all the strings together
 .T                       Transpose, without chopping off overhang
  (Q implicit)

Pyth - 3 bytes

Very simple, will add expansion later, on mobile.

s.T

Test Suite

s                         Join all the strings together
 .T                       Transpose, without chopping off overhang
  (Q implicit)

#Pyth - 3 bytes

Very simple, will add expansion later, on mobile.

s.T

Test Suite

#Pyth - 3 bytes

Very simple, will add expansion later, on mobile.

s.T

Test Suite

s                         Join all the strings together
 .T                       Transpose, without chopping off overhang
  (Q implicit)