your're going to need some serious firepower to go up against a 20th caster with a binder, now don't get me wrong, Binder is one of my favorite classes, but it's no wizard...
Binder20//black ethergaunt20 you can hangout on the etherial plane, and spam binder abilities(Zceryll's summon monster as a 20th lvl Sorcerer)
(leaves room forPRC's(KoSS)) LA buyoff allowed?- reason being Black ethergaunt casts as 17th lvl wizard, so if u can buy off....
also with the black ethergaunt's Total Vision ability, he can "discern all objects within 40 feet, even through the mask that hides its face..." would this get around the SCM's illusions? esp tricky, if he has his illusions at over 100% "real"- whatever that means...
what about cohorts? leadership? blowing your entire wealth by level to hire help for one day allowed?
Binder20//Druid5,Planar Shepherd10,Druid5: pick the region of dreams for the 10-1 time ratio: again spam binder abilities(30 rounds buff time while he gets 3 ha)
that's 6 uses of Zceryll's summoning + all your daily wildshape uses for outsider sp, or su's + some summon nature's ally 9's maybe?
Initiate of Nature feat lets you rebuke plants + that vestige that can rebuke, could fuel some Divine MetaMagic....
venerable dragonwrought kobold if you need the +3 to mental stats....
Divine Minion Template at LA +1 to add 11HD worth of wildshape on the druid side, this puts over 30HD outsiders / dragons into range
wait, with abberant wildshape you can Wildshape into a black ethergaunt if need be-
also an animagic field only has a range of 10ft, maybe you can use that dirt and elder earth elementals to bury him(remember10-1 time ratio)
edit: you could creative with this, focusing on spells/abilities that net you more actions/round, that also can outlast a wizard in an encounter
like the time ratio abuse + summoned pixies flying around dumping out water..(whats that item that never runs out of water?) hang out on the etherial plane
or burrowing as a wildshaped longhorn minotaur(swims through earth) wait for the enemy to drown in the quicksand..
box him in with walls of force, (fill with water),
throw eversmoking bottles everywhere so you can't see his fear attacks, and he cant see you... you can't see his illusions
combine invisible spell with summon spells
point is 30(29) rounds should be plenty of time to set up shenanigans