summons get stronger as you get stronger they have oh lets say your stats x1.5
and at certain milestones they upgrade liek right away with dogs you get one little puppy sorta liek inuzuka and for others you egt a tiny baby summon at like 1k nin it become a kid 2k young adult 4k adult 6k huge ones
and teh growing with you helps caus ei know summons are strong but after a while when everyone become super strong summons would be weak in comparison
