Rhydon

Rhydon possesses a very important place in RBY OU thanks to a fairly unique typing and formidable Attack stat; moreover, its Earthquake is the most powerful physical attack in the game without a drawback. Rhydon's typing gives it a good amount of defensive utility, such as switching in to force and punish Hyper Beam recharges, taking Explosions, staving off Thunder Wave, and stonewalling Zapdos and Jolteon. Thanks to its immense Attack stat, Rhydon can hit very high damage ranges, most notably a guaranteed 2HKO on Chansey. It's also capable of KOing Tauros after two Body Slams from your own Tauros. This power makes it very difficult to switch into, with would-be checks such as Exeggutor taking surprising damage. While initially slow, Rhydon is also very scary for paralyzed teams to fight—they often fold to it outright. Naturally, this means it appreciates paralysis support from teammates such as Chansey. It can still outspeed Slowbro and Snorlax, however, to force damage if they lack Reflect.

Golem has competed with Rhydon for a teamslot for many years. Golem has the strongest Explosion in the game, only beaten by Snorlax's Self-Destruct, along with slightly higher Speed to win against Rhydon specifically. However, because Golem's niche hinges on Explosion, it often has to eschew Substitute. The lower damage output also causes Golem to lose out on some very valuable ranges, notably losing to Reflect Chansey more often than not, which Rhydon excels against. Due to these factors, Rhydon is generally favored over Golem in the metagame.