First you need to jack into tamakos Hp use th short cut and then head for undernet4To get to undernet4 you have to go strait from undernet2. You DO NOT go back to undernet1. go to the closed portal on the left then do not use that move thingie keep going and you sould see another one use that and then you go up you should see a navie beheind himm thats the way to undernet4 hope it works

start from the postman(purple navi thingy) and go down till you see a red thingy that
moves you left ride it then you should see a yellow and blue warpy thing use it go right
and you should see a red thingy that moves you right dont use it i repeat DO NOT USE IT
instead go upthen keep following the path till you see a red thingy that moves you right
use it then go up aaaaaannnnndddd chuck ching well not yet you should see a purple bad
navi talk to him hell say "yeah, you look strong enough fer the under!go on in!" and then
your in under net four ill leave it to you to find the navi ranked 3 i really do hope this
helps! it took me forever in fact i found it by accident

if your still confused try these maps http://faqsmedia.ign.com/faqs/image/megaboy_mbn3_Undernet_1.gif