These things are TANKS. They can have insane health (my best one has over 600k) and do an absurd amount of damage (the best I've gotten is 20k-21k). They have slow stamina drain, but even slower stamina recovery (although it always seems to fill quickly when I'm not watching). They have good weight even at low levels; both of mine sit a around 1300. They can harvest a lot of hide and meat. They're great for leveling your character and for leveling unborn reapers. They have a really good jump considering their size. They don't have a saddle but they do have a natural damage reduction.
Lure a Reaper Queen into a metal trap WITH A COVERED FLOOR SO IT CANNOT ESCAPE AFTERWARDS, that way multiple people can get pregnant from 1 good Queen. These other beach noob comments forget that detail. Using glowpets to weaken her, damage her until she reaches 2k hp, preferably with a Megalo or Reaper, but Drakes work too. Turn the lights off and she'll glow pink, showing she's ready. Now dismount and stay just out of reach until she leans forward, at which point she'll try to pick you up and BAM you're pregnant. There's a Drake trick that works without dismounting, look it up. Use the next 12 hours to trap more Queens, finishing them off with a shotgun to get the most exp for the baby. Once time is up, encumber yourself with meat in a small room and let the baby kill you when it hatches. It'll take all the meat regardless of weight and you won't have to handfeed it at all, pheromones are worthless lmao. Use a crab to pick the baby up and it'll stay there until it hits juvenile.