In today's damage calcs, the role of Obstagoon will be played by Raticate.
Vs
Snorlax Hyper Beam vs. Raticate: 79-94 (22 - 26.1%) -- 6.9% chance to 4HKO
+1 Raticate Double-Edge vs. Snorlax: 197-232 (37.6 - 44.3%) -- guaranteed 3HKO
Snorlax Earthquake vs. Raticate: 142-168 (39.5 - 46.7%) -- guaranteed 3HKO
+1 Raticate Hyper Beam vs. Snorlax: 294-346 (56.2 - 66.1%) -- guaranteed 2HKO
-Switching into a Snorlax's Hyper Beam and Sharpening on the recharge turn is what Obstagoon is built for, but he needs at least 44% damage on it to avoid taking a big hit from EQ, and it can't 2HKO lax from full without crits or exactly highrolls on exactly Double-Edge and Hyper Beam.
Vs
Tauros Hyper Beam vs. Raticate: 74-88 (20.6 - 24.5%) -- guaranteed 5HKO
Tauros Earthquake vs. Raticate: 134-158 (37.3 - 44%) -- guaranteed 3HKO
+1 Raticate Rock Slide vs. Tauros: 118-139 (33.4 - 39.3%) -- guaranteed 3HKO
+1 Raticate Hyper Beam vs. Tauros: 234-276 (66.2 - 78.1%) -- guaranteed 2HKO
-Tauros is much less bulky than lax, so it can be KO'd at earlier percentages, and +1 Rock Slide into Hyper Beam is >99% chance to 2HKO from full, But it is very risky to switch in and boost against a non statused bull, as crit EQ can KO after Hyper Beam. Where Obstagoon might shine against a healthy Tauros, is subverting the Tauros mirror.
Raticate Hyper Beam vs. Tauros: 155-183 (43.9 - 51.8%) -- 11.1% chance to 2HKO
-Two Tauros Body Slams on another Tauros deals on average ~58%. Meaning, if 2 full health Taurous Body Slam each other twice, and one clicks Hyper Beam as the other switches out for goon, the one stuck recharging is nearly always going to be in goon's safe KO range. Rhydon, TTar and Escavalier cannot say the same, despite having higher attack stats, because they don't have STAB Hyper Beam.
Vs
+1 Raticate Rock Slide vs. Cloyster: 149-176 (49.1 - 58%) -- 98.4% chance to 2HKO
Cloyster Blizzard vs. Raticate: 174-205 (48.4 - 57.1%) -- 93.5% chance to 2HKO
Cloyster Surf vs. Raticate: 275-324 (76.6 - 90.2%) -- guaranteed 2HKO
-Surf Cloyster can very likely Revenge Kill a goon that has taken Hyper Beam chip to set up, and Obstagoon can't 2HKO Cloyster without a boost.
Vs
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+1 Raticate Earthquake vs. Rhydon: 180-212 (43.5 - 51.3%) -- 6.4% chance to 2HKO
Rhydon Earthquake vs. Raticate: 241-284 (67.1 - 79.1%) -- guaranteed 2HKO
+1 Raticate Earthquake vs. Tyranitar: 190-224 (47.1 - 55.5%) -- 77.3% chance to 2HKO
Tyranitar Earthquake vs. Raticate: 165-194 (45.9 - 54%) -- 48.6% chance to 2HKO
-Other Rock types can be/are problematic for Obstagoon, since it has way lower bulk than they do, and needs a boost or a crit to threaten a 2HKO. Rhydon is especially good at shutting down goons, even if it got an optimal setup.
Vs
+1 Raticate Body Slam vs. Exeggutor: 142-168 (36.1 - 42.7%) -- guaranteed 3HKO
Exeggutor Psychic vs. Raticate: 169-199 (47 - 55.4%) -- 74.8% chance to 2HKO
+1 Raticate Rock Slide vs. Exeggutor: 125-148 (31.8 - 37.6%) -- 92.9% chance to 3HKO
+1 Raticate Hyper Beam vs. Exeggutor: 251-295 (63.8 - 75%) -- guaranteed 2HKO
Vs
Starmie Surf vs. Raticate: 306-360 (85.2 - 100.2%) -- 2.6% chance to OHKO
Starmie Psychic vs. Raticate: 143-169 (39.8 - 47%) -- guaranteed 3HKO
+1 Raticate Hyper Beam vs. Starmie: 251-295 (77.7 - 91.3%) -- guaranteed 2HKO
-Surf and Hydro Pump variants can completely shut down Obstagoon, and Crit Psychic will likely KO a chipped goon. Hyper Beam crit will OHKO Starmie, but Starmie has higher chances of winning this matchup just by virtue of speed.
Vs
+1 Raticate Hyper Beam vs. Chansey: 621-730 (88.3 - 103.8%) -- 25.6% chance to OHKO
+1 Raticate Rock Slide vs. Chansey: 311-366 (44.2 - 52%) -- 14.3% chance to 2HKO
Chansey Ice Beam vs. Raticate: 117-138 (30 - 35.4%) -- 26.9% chance to 3HKO