This is a very minor point, I'm wondering what warrants Buneary in D-tier? It's got a bit of utility for sure, but the starting 0 happiness putting evolution way off should surely make it nigh-unusable, and surely not better than Stunky or Wingull. Has anyone used it? I know it's the difference between calling it crap and rubbish but it did stick out to me
I've got a suggestion to fix this shortcoming. DP got a friendship underflow bug. If you use 1 Energy Powder or Energy Root right after catching Buneary during a battle, it will underflow the friendship. So that's instant Lopunny after a level-up and maxed Return after Lost Tower. I haven't used this myself yet, but it's documented
here. The bug seems to have been fixed in Platinum though.
It would improve the performance of Golbat, Togepi, Budew, Chingling, Munchlax and Riolu as well, though it will take 8 uses for them.
Might even be worth using on other Pokemon as well. A fast maxed out Return as a coverage option is very neat.