The Door of Night vs. the following
The following characters are banished through the Door of Night (J. R. R. Tolkien) and must return to reality. They all have standard equipment but cannot call for outside help. They have unlimited time to try, in their banishment they are functionally immortal (time does not pass) and they have no need for sustinance (i.e. Galactus is at full power levels.) Who can make it past the Door?
I say Spiral can do it, she teleports across dimensions. If not her than definitively Loki.