User blog comment:AnonymousDuckLover/Joke Smash Characters: Igglybuff/@comment-25093165-20150520200946/@comment-5814264-20150520230853

The purpose of Igglybuff being invincible during Rest is actually meant to mock the card game where certain baby Pokémon are invincible when sleeping. It was either that or making it so that 50% of attacks missed Igglybuff, but that just seemed overpowered. The healing part was more obviously a nerf to rest so that it doesn't do any knockback or damage, but still have it do something, while also more closely following the move in the game, though I guess the invincibility frames could be taken off while Igglybuff is falling asleep and walking up.

More speed on rollout? Maybe less speed to make the move easier to control and better reflect younger Pokémon being slower.

I also can't believe I forgot to put in sing, even after literally copying and pasting Jigglypuff's SSB4 page here, then editing the changes from Brawl section to better reflect Igglybuff. Though the nerf for Sing seems a bit too much, though you never know until you actually create the character and actual test it.

The main point of Igglybuff was to jokingly be a buffed Jigglypuff.