White is in a world of trouble, with two groups on the verge of capture. Do your best! Thanks to Piccolo for pointing out a few problems in the original version.
(;AW[ra]AW[mb]AW[ob]AW[pb]AW[nc]AW[pc]AW[pd]AW[qd]AW[pe]AW[se]AW[qf]AW[rf]AW[sf]AB[la]AB[oa]AB[pa]AB[kb]AB[nb]AB[qb]AB[rb]AB[lc]AB[qc]AB[sc]AB[kd]AB[md]AB[rd]AB[sd]AB[me]AB[oe]AB[qe]AB[re]AB[nf]AB[pf]AB[pg]AB[qg]AB[rh]AB[qi]C[Nothing but your absolute best will do.]SZ[19]PL[W]
(;W[sb];B[sa]LB[nh:X]C[Ko. Please make a ko threat by playing at X.FORCE];W[nh];B[mh]C[Black answers the threat.]
(;W[sb];B[qa]C[Now suppose black has no threats bigger than the value of the ko, but black is determined to resist.]
(;W[na];B[sa]C[All for nothing.])
(;W[rc];B[sa]C[Black is fighting hard. Make another ko threat at X, or play locally if you want to.]LB[ni:X]
(;W[na];B[sc]C[Black wins the ko.]
(;W[rd];B[ma]
(;W[nb]C[Bingo.RIGHT])
(;W[sd];B[nb]LB[ni:X]C[Make another ko threat at X if you need to, or play locally if you like.]
(;W[sb];B[na]C[You can't make a 2nd eye.])
(;W[ni];B[mi]C[Black answers.];W[na];B[mj]C[Black hasn't got any good threats, so makes a smaller one somewhere. Go ahead and connect the ko.];W[nb]C[Black's corner group is dead, but you did not have to allow a 2nd ko. You ended up using a ko threat unneccessarily.])))
(;W[sd];B[rd];W[re];B[rc]C[You have snatched defeat from the jaws of victory.]))
(;W[ni];B[mi]C[Black answers.]
(;W[na];B[sc]
(;W[rd];B[sd];W[sb];B[sc];W[sd];B[sb];W[ra]C[Why did you even fight the 2nd ko?])
(;W[sd];B[rd];W[re];B[rc]C[You have snatched defeat from the jaws of victory.]))
(;W[ra]C[Black makes a small threat somewhere.];B[nj];W[na]C[Alive, but you didn't need to fight the 2nd ko. Why waste threats?])
(;W[sc];B[na]
(;W[ma];B[mc];W[ra]C[Alive, but you did not need to fight the 2nd ko. Why waste a ko threat?])
(;W[ra];B[ma]C[You could have done better,])))
(;W[sc];B[ma]C[]LB[ni:X];W[na];B[ni]C[Black makes a small threat somewhere.]
(;W[ra];B[oh]C[Black follows up his small threat. You live, but there was no need to allow that 2nd ko.])
(;W[nb];B[oh]C[Black follows up his small threat. You live, but there was no need to allow that 2nd ko.])
(;W[lb];B[nb]
(;W[mc];B[na];W[ra];B[ka]C[This is not the best you could have done.])
(;W[ra];B[mc];W[na];B[oh]C[Now black gets around to following up that little ko threat. You did not have to allow a 2nd ko.])))
(;W[rd];B[ma];W[sc];B[na]C[Alive, but you could have done better.])))
(;W[na];B[qa]C[You have snatched defeat from the jaws of victory.]))
(;W[na];B[qa]
(;W[sb];B[sa]C[Black lives, and you die.])
(;W[sa];B[sb]C[Black lives, white dies.]))
(;W[sa];B[qa]
(;W[na];B[sb])
(;W[ma];B[na]C[Now what?]))
(;W[sg];B[sh]C[Um, you're not seriously trying to get out are you?])
(;W[rg];B[sg]C[???])
(;W[od];B[nd]
(;W[mc];B[oc]C[Nope.])
(;W[oc];B[mc]C[Nope.])))