Fully Evolved Pokemon guaranteed to live at least 2 crit slashes from oak's L50 scyther (brackets = how many they can live guaranteed; possibly more if good DVs)

Cloyster (2)
Onix (4)
Golem (4)
Omastar (4)
Weezing (2)
Rhydon (5)
Tangela (2)
Sandslash (2)
Slowbro (2)
Kabutops (3)
Poliwrath (2)
Dragonite (2)
Lapras (2)
Snorlax (2)
Aerodactyl (2)
Articuno, Mew, Mewtwo (Kappa) (2)


Pokemon that are close to surviving 2 / will survive with good ranges and/or non-0 DVs:
Kingler (MaxHP 115 at 0 HP DV, max damage to 0 DV def = 62)
Marowak (MaxHP 120 at 0 HP DV, max damage to 0 DV def = 65)
Blastoise (MaxHP 139 at 0 HP DV, max damage to 0 DV def = 71)
Pinsir (MaxHP 125 at 0 HP DV, max damage to 0 DV def = 71)
Tauros (MaxHP 135 at 0 HP DV, max damage to 0 DV def = 74)
Nidoqueen (MaxHP 150 at 0 HP DV, max damage to 0 DV def = 81)
Exeggutor (MaxHP 155 at 0 HP DV, max damage to 0 DV def = 83)
Kangaskhan (MaxHP 165 at 0 HP DV, max damage to 0 DV def = 87)