http://www.youtube.com/watch?v=U3PU0IMRuBs
Main riff:
G----------------------------|
D--------------------7-5-----|
A------------------6-----6-5-|
E-0-0--0-0--0-0--5-----------|
Variation #1:
G--------------------------------|
D----------------12-12-13p12-----|
A----------------------------12\-|
E-0-0--0-0--0-0------------------|
Variation #2:
G-------------------------------|
D-------------------13-------11-|
A----------------12----12-12----|
E-0-0--0-0--0-0-----------------|
Variation #3:
G------------------------------|
D---------------------13----11-|
A------------------12----12----|
E-0-0--0-0--0-0--0-------------|
Chorus:
G-------------------------------------------|
D-------------------------------------------|
A-------------------------------------------|
E-5-5--5-5--5-5--5-5--5-5--5-5--5-5--5-5--3-|
G----------------------------|
D--------------------7-5-----|
A------------------6-----6-5-|
E-0-0--0-0--0-0--5-----------|
[ Tab from: https://www.guitartabs.cc/tabs/p/porcupine_tree/halo_btab_ver_3.html ]
Bridge:
G-----------------------------------------|
D-----------------5-7---------------------|
A-5-7---5-7---5-7-----5-7---5-7---5-7-----|
E-----0-----0-------------0-----0-----6-5-|
G----------------------------------------------|
D----------------------------------------------|
A------------------------------------------5-4-|
E-3-0-0--3-0-0--3-0-6-5--3-0-0--3-0-0--3-0-----|
Post-bridge:
G------|
D------|
A------|
E-5----|
Outro:
G---------------------------------------------|
D---------------------------------------------|
A---------------------------------------------|
E-5-5--5-5--5-5--5-5--5-5--5-5--5-5--5-5--3---|
G-------------------------------------------------------|
D-------------------------------------------------------|
A-------------------------------------------------------|
E-0-0--0-0--0-0--0-0--0-0--0-0--0-0--0-0--0-0--0-0--0-0-|
G-------------------------------------------------------|
D-------------------------------------------------------|
A-------------------------------------------------------|
E-5-5--5-5--5-5--5-5--5-5--5-5--5-5--5-5--3-3--3-3--3-3-|
G----------------------------|
D--------------------7-5-----|
A------------------6-----6-5-|
E-0-0--0-0--0-0--5-----------|