http://replay.pokemonshowdown.com/smogtours-gen1ou-54833

turn 1 - metalgross does the right thing switching in chansey to take psychic/twave, although going egg to keep up the pressure and get sleep is viable too.

turn 2 - sg wants para on chansey clearly, which is fine. metalgross keeps chansey healthy but i think he should just go egg anyway unless he's running dash lord sing chansey ;]

turn 3 - sg doing the right thing pressuring the chansey. WTF is metal doing going to zam tho? It doesn't do anything useful or draw out a particularly key move. SG has no reason not to psychic/stoss/twave there.

turn 4 - it's revealed metal used that zam switch to relieve the specfall on chansey. Passable play then.

turn 5-10 - sg pressures chansey, no reason not to, since metal can't twave it since it'd block sleep. wtf is metalgross doing fishing for freeze though when it's a really uncomfortable position for chansey - he risks getting lucked out in order to get the freeze advantage. However, if he can PP stall zam's psychic (possibly but gonna be costly in terms of damage to metal's own zam, + risking being lucked out) then the freeze advantage can be made use of.

turn 11-14 - why is metalgross para-ing the opposing zam when it blocks sleep? idgi! anyway, sg has played flawlessly pretty much thusfar.

turn 15 - sg's first misplay, switching out a 30% zam that can't block sleep any more! He should have recovered off a bit to let it be a nice sleep absorber rather than trying to be aggressive like that.

turn 16 - metalgross predicts the eq of lax's (aiming for gar) and uses it to gain sleep advantage. The correct play here is to psychic with egg in metal's case, since sg left zam in range of being 2HKOd by psychic, and lax can't eat psychic easily, since crits are hugely painful for it.

turn 17 - so to recap, by this point, both metalgross and sg have managed to let all of their mons that block sleep potentially get weakened to the point where they can't do this any more (metalgross's chansey/zam, sg's zam). Metalgross makes the right play, and sg goes egg, trying to absorb sleep (sensible). Neither player can realistically block sleep if their opponent uses psychic next turn, but using psychic means the opp can easily gain sleep advantage. Overall, a predictive coinflip because of misplays earlier on!

turn 18 - both go zam. No comment, as I said before, predictive coinflip.

turn 19-27 - no misplays, just bad luck for metalgross - however, stoss zam should generally beat non-stoss zam a larger proportion of the time in a 1v1.

turn 28 - sg chokes again! he needs zam healthy to block gar/egg's sleep (and force one to explode as a probably consequence) but instead risks it versus lax, taking huge damage and stopping it being able to function properly, all for paralysis vs lax, which is not terribly valuable (sure better than no status, but not worth risking the health of a sleep blocker for. SG should have switched lax in instead.

turn 29 - i would rather switch in lax than bro, since metal's last is probably tauros, and being able to para it is always a huge advantage. Lax switches in pretty comfortably in mirrors, as does bro into lax, but lax is less valuable at a glance. Maybe Lax can break the team open easier, but being able to win in what may be a tauros ditto-like situation in the endgame is valuable in my eyes here.

turn 30 - I don't know what lax was going to do.. explode maybe? There's a few different ways to try and beat bro, and staying in there is not bad.

turn 31 - wtf are you doing sg! Without even an Amnesia up he sends slowbro to sleep, vulnerable to the attacks of pretty much everything not named exeggutor.

turn 32 - bad luck metalgross, and sg going lax there is a pretty solid play, it gets a free attack, although if metalgross is clever/lucky? he can reduce the damage with a correct prediction. Egg or Gar (one of the two) can come in without taking much damage and basically guarantee - gar can in particular, as bro doesn't block sleep either due to tbolt.

turn 33 - free hypnosis, tbolt/ns if something threatening comes in.

turn 34 - lucked, but I would have tried to absorb with something less valuable than a healthy lax if i were sg. =/

turn 35 - sg should probably have gone bro to take the sleep powder, as it's not really an abusable switch (bringing bro in) as egg can hardly touch it and nothing can switch in and scare it enough to avoid it waking up and being a para-spreading threat!

turn 36 - lax was a better switch, since it blanket covers pretty much everything that could ever come in, and it aggressively would punish sg for keeping a sleeping mon in, were he to do so.

turn 37-38 - risky but nessecary in the circumstances by metalgross, perfectly acceptable plays by sg.

turn 39-40 - sg hurts lax, making it tempted to explode on the subsequent turn.

turn 41 - metal reveals rest,  as sg tries to absorb a possible explosion with zam (fine play I guess)

turn 42 - going for the recovery on zam is sensible since it walls half of metal's remaining team, but alas, fp.

turn 43 - turn lax wakes, zappy is clearly the best threat at this point in the match to destroy the lax. Chansey comes in to try and recover versus zam, and isn't awful to have out vs zapper but if metal gets at all unlucky it could lose him the game, should he take a drill peck and it crit or he fp.

turn 44 - metal is not unlucky this turn :) correct play by both although going to lax to take the dpeck might well have been safer.

turn 45-48 - sg gets some helpful luck (a crit woulda been fine too at any point) and lax is down.

turn 49-51 - metal is outta options and takes on zappy in the only way he can. SG might as well stay in and spam drill peck, his odds of breaking chansey are good. Metal lets chansey go down, and puts all his faith in his tauros, as a true RBY player does.

turn 52-53 - zam is right mon to sack, blizzard is right move to take down zapdos. Right play by both

turn 54-57 - metal lucks out and freezes lax.

turn 58-59 - hoping for tauros to crit is fine. both play fine

turn 60 - egg taking para is probably wiser than letting tauros take it, I agree w/ metal's play.

turn 61 - preserving bro is fine, since it means sg might have better than a slightly nicely in his favour 50/50 to win the match (see: tauros ditto with a sleeping egg and a just usable zapper in the back)

turn 62-64 - I would sack zapdos personally and force the tauros ditto. Egg is still usable to try and wake up later on, but eh, either way it looks like it's becoming a 50/50 - so maybe SG should have tried to amnesia up with bro rather than wake up egg! Either way, the game is heading towards a tauros ditto.

turn 65-68 - sg should force the tauros ditto! instead he risks and loses bro, putting him in a bad place.

turn 69 - tauros ditto no comment

turn 70 to end - absorbing hb with egg is smart, he had ~50% chance to get sleep, and thus straight up win. Overall metalgross's chance to win in this endgame is like ~75%.