(updated 11/30/18)
Martyr Proc sideboarding guide:
vs humans:
-1 copter
-1 crucible
-1 ascendant
-1 ballista

+2 burial
+2 prison

vs spirits:
-1 crucible
-1 ascendant
-1 ballista
-1 ranger
-1 proc

+2 burial
+2 prison
+1 spyglass

vs dredge:
-1 ascendant
-1 dusk
-3 cast out
-1 copter
-1 crucible

+2 surgical
+2 prison
+2 burial
+1 rip

vs hardened scales:
-1 ascendant
-1 crucible
-4 copter
-1 ballista
-1 cast out

+2 stony
+2 burial
+2 prison
+1 disenchant
+1 spyglass

vs burn:
-1 dusk
-2 cast out

+3 gideon

vs phoenix:
-1 ascendant
-1 ballista
-4 copter
-1 wrath

+1 sphere
+2 surgical
+2 prison
+2 burial

vs hollow one:
-1 ascendant
-1 ballista
-1 dusk
-1 crucible
-2 copter

+2 surgical
+2 prison
+2 burial

vs tron:
-1 Wrath
-1 Settle
-1 Dusk
-1 Kami
-2 proc
-1 avacyn
-1 ballista
-1 path
-1 ranger

+3 Gideon
+2 Stony
+2 Surgical
+1 Spyglass
+1 Sphere
+1 Disenchant

vs KCI:
-1 wrath
-1 dawn
-1 settle
-1 kami
-2 proc
-1 ballista
-1 avacyn
-1 copter
-1 ranger

+2 stony
+2 surgical
+3 gideon
+1 sphere
+1 rip
+1 disenchant

vs storm:
-1 wrath
-1 dawn
-1 settle
-2 proc
-1 kami
-3 cast out

+1 rip
+1 sphere
+2 surgical
+3 gideon
+2 prison

vs titanshift:
-1 wrath
-1 settle
-1 kami

+3 gideon

vs infect:
-1x martyr
-1x dusk

+2 prison

vs boggles:
-1 path
-4 copter

+2 burial
+2 prison
+1 disenchant

vs whir:
-3 sweepers
-1 kami
-2 proc
-2 path

+2 stony
+1 spyglass
+1 disenchant
+3 gideon
+1 surgical

vs UW:
-1 kami
-1 wrath
-1 settle
-3 path

+3 gideon
+1 spyglass
+1 disenchant
+1 surgical

vs GB:
-1 kami
-1 ascendant
-1 settle
-1 flagstones
draw: -1 copter/+1 burial

+3 gideon
+1 spyglass

vs Jund:
-1 kami
-1 settle
-1 flagstones
-3 copter

+3 gideon
+2 burial
+1 spyglass

vs mardu:
-1 kami
-1 dusk
-1 settle
-4 copter
-2 proc
-1 wrath

+3 gideon
+1 rip
+2 surgical
+2 prison
+2 burial

vs GDS:
-1 wrath
-1 settle
-1 ascendant

+3 gideon