The community consensus is that in every 15 packs, 10 will contain an uncommon bonus sheet card, four will contain a rare, and one will contain a mythic rare
However, there is no information on how it was distributed
P - Psy Ball 30+ This attack does 30 more damage for each Energy attached to both Active Pokmon
If you're more interested in really big numbers rather than watching numbers go up, check out the most expensive MTG cards of all time
Named characters are better for brand recognition though, so I think we should expect a ton of legendary creatures in UB sets from here on out
Just like Eternal Witness is usually more powerful that Regrowth because you can abuse the creatureness of it, you can flicker, bounce, or recur this for more and more lands (maybe even cards!)