Jay Buhner - 3 times, 1995, 1996, 1997. 44 was his highest in 1996
Putting these two guys together because, well, they were a big part of the Mariners success in the 90s. Buhner managed the feat three times in his career, going 40/44/40 in three straight seasons. He struck out a lot, but had a great eye at the plate still as he put together a slash line of .259/.367/.542 with a 132 OPS+ over that stretch. He made his lone All-Star game in 1996 as well. Overshadowed by some of the other hitters on the team, The Bone stood out for his fun personality, strong arm, power bat, and big ol bald head that inspired countless kids (myself included) to shave their heads.
Alex Rodriguez - 4 times, 1996, 1998, 1999, 2000. 42 twice in 1998 & 1999
Bret Boone was tough to root for, but that pales to the emotions that bubble up when speaking of Alex Rodriguez. He was amazing to watch while he was in Seattle, bursting onto the scene in 1996 at the age of 20. He would hit .358 with 54 doubles and 36 homers, turning in one of the best seasons ever... and essentially doing it as a rookie.
He would go 42/42/41 over those last three years in Seattle. I remember at the closing ceremonies of the Kingdome, A-Rod said something along the lines of Seattle being the last place he wanted to play growing up. Maybe that's wrong, and maybe it was my way of finding another reason to dislike the guy. He would go on to dominate in Texas and New York during the regular season, and we had to watch the highest paid player in baseball dominate, all the while not in Seattle.
156 homers in three years in Texas, 351 in 12 years in New York, and 189 in seven years in Seattle. He was a lot of fun while he was here, and for now, I'm going to remember just that about him, instead of the reported steroids and money-grabbing antics.