Here, we have Manaphy from Majestic Dawn. Although it has some interesting attacks, its pre-evolution Phione was a more effective starter from the set.
HP of 70 is OK for a non-evolving basic (better than Sableye SF and same as Pachirisu GE), weakness to Lightning is bad, especially from an early Flash Impact from Luxray GL, and retreat cost of 1 is OK and expected.
Aqua Skin is a nice Poke-Body to heal Manaphy a bit. However, with that uninspiring HP, Manaphy won't be able to take up the tanking role. More often than not, Aqua Skin can only be useful against attacks that do 10-20 damage (often from evolving Basics). Even then, most starters (such as Gastly SF, Sableye SF, Trapinch SW, for example) today do not really aim for damage but for faster set-up or disruption.
Chase Up is an unreliable attack. Although having any card from your deck can be useful, the flippiness of it makes it bad as a starting attack. If you want to get any card, you might as well use Jirachi RR (which has a useful attack in Detour to boot).
Fountain provides decent energy acceleration but the fact that you need to attach 2 Water energies to Manaphy beforehand ruins its potential. It is good to note, though, that it is the one of the few Water Pokemon that is able to directly attach Water energies. However, it is inevitable that Manaphy would be Knocked Out anyway so why waste 2 energies on this one when you could have attached the energies to your main attacker.
All-in-all, an interesting starter, but far too unreliable to be a set-up starter in today's metagame.
Modified- 3.5/10 (outclassed by other starters, which incidentally do not get used very often nowadays, except for Sableye in Gyarados)
Limited- 8/10 (Fountain can make for great energy acceleration. Chase Up is not that bad for an attack that can search any card here, despite the flippiness)
