select w.id,
p.age,
w.coins_needed,
w.power
from wands w
JOIN wands_property p
on w.code=p.code
where p.is_evil=0
and (p.age,w.coins_needed,w.power) in
(select max(p.age),min(w.coins_needed),max(w.power)
from wands w
 join wands_property p
 on w.code=p.code
 where p.is_evil=0
 group by w.power, p.age
)
order by w.power desc, p.age desc