Ratio wise, what healing item recovers the most HP but costs the least?

Question

I'm trying to get through the Elite Four of Sinnoh. Please don't list items like Max Potion and Full Restore, which heal all of your Pokemon's HP.

Answer 1

In Generation 4, the fresh water and energy root are tied for cheapest HP restoration, costing P4 per HP restored.
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Answer 2

Energy root would be your best option here. Though fresh water has the same hp/PK$ ratio, energy root it more practical in literally every way. You can buy multiple at once, it heals more at once, and as said before it is the cheapest. However keep in mind if you have friendship related moves, using them will lower your friendship level, and you 'might' be better off using fresh water.

tl;dr: Use energy root, unless you are worried about friendship, then use fresh water.

Comments

Does this add anything important the other answer doesn't have?

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Yes, the friendship value. If they are using moves on their mons that utilize friendship (ie, return/frustration), then even though the root heals a lot, it might not be worth it. It also tells them which is more time consuming, though they should know that already.