Entei

Boasting good overall stats, Entei is a solid choice that can take a few hits and maintain good offensive pressure. Entei is a great attacker that makes itself worthwhile with its respectable bulk and solid offensive movepool; specifically, Sacred Fire, Entei's signature move, has a solid 100 Base Power and a 50% chance to burn, deterring physical attackers from switching in. Entei also works as a good sun counter, being able to OHKO both Mega Charizard Y and Venusaur while taking little damage from their attacks. Adding to that, when holding Safety Goggles, Entei is immune to Sleep Powder and can get the KO on Venusaur. However, it loses to threats most other Fire-types would lose to as well. Landorus-T is a cold stop to Entei, although switching in on Sacred Fire is risky for it. Entei also can't touch Heatran or Mega Diancie, while they hit it hard with Earth Power and Diamond Storm, respectively. While Entei has no spread moves to bypass redirectors, besides the suboptimal Snarl, Sacred Fire and Stone Edge allow it to take on the three most common redirectors, namely Jirachi, Amoonguss, and Togekiss. With Safety Goggles, Entei can ignore Amoonguss completely. Be wary, though, as Entei has difficulties switching into attacks it doesn't resist. Lastly, Entei is sadly often outclassed by other Pokemon because of its average stats and movepool, as it faces competition from Talonflame as a strong physical attacker and from Heatran as a Substitute attacker.