Nobody was comparing Manaphy's attack vs Darkrai's attack, or, at least, I didn't.
If we are are compare and contrast two cards, then we need to look at the
entire card, not just a single aspect. Many cards have have something good about them but fall short because the rest of the card lets down the best bits. Even two cards that are equally successful may not be used in the same way due to their inherent differences. More relevant than the attack though is the HP;
Darkrai-EX is better at taking a hit unless we get into specifics (namely taking a blow from a Fighting-Type).
Comparing Shaymin EX, Manaphy EX and Darkrai EX is not right.
Why is it not right?
To get an idea of how a card will be used, one looks at similar cards from the past.
Darkrai-EX has a similar Ability to
Manaphy-EX while
Shaymin-EX (ROS) has a similar size and status (a small Pokémon-EX on your Bench). Looking at how these pieces function on existing cards will not tell us exactly how a new card made up of such things (especially with other alterations) will function, but it certainly gives us an idea and is a solid starting point.
In case Manaphy EX is forced to the active spot it would likely not hurt at much as you might think. If it does survive a turn in the open it still has the free retreat cost ability.
The question is whether or not 120 HP is likely to survive being attacked, and unless you're facing one of the weaker control decks or have some other mitigating factor, the answer is "No 120 HP is not likely to survive being attacked." It would require a major shift not just in specific decks, but dominant tactics. I do recognize this is a possibility; I've been more focused on Expanded than Standard (if we are talking Expanded as well, then yes,
Manaphy-EX will rarely fall outside of OHKO range if an opponent has even a half-decent field).
Also it depends on the deck It's used in. For example it wouldn't burden in a deck using Golduck Break and splash energy.
Did I get bad translations for these cards, or are two different points kind of running together?
Golduck BREAK does help make use of
Manaphy-EX because it would allow a basic
Water Energy to bounce from Pokémon to Pokémon, a familiar tactic used in other Energy transfer decks. As we are discussing an opponent promoting and taking out
Manaphy-EX (or just taking it out on the Bench if
Greninja BREAK proves worthwhile), that doesn't help; as stated I believe
Manaphy-EX is quite likely to be taken out in a single shot, so it can't retreat after being KOed.
Splash Energy is a Special Energy card, so only a few forms of Energy acceleration work with it; for example
Golduck BREAK does
not. Most of the time you'll have to burn a manual Energy attachment to apply it to a card; not a deal breaker, but relevant to considering it with
Manaphy-EX. You'll need to prep
Manaphy-EX with a
Splash Energy ahead of time because again, more often than not
it will be OHKOed if it is forced into the Active slot by your opponent. Now the question becomes "Will my opponent want me to take a chance and Bench it again?" The main defense
Manaphy-EX has is that it might not be the best thing to focus on attacking. That's really it; if it proves to be a good target, an opponent forces it if able and takes the KO, and may even hope you drop another (or the same copy if reclaim it) so they can do it again. Also... Special Energy cards are the easier ones to discard.
We already see something like this with
Shaymin-EX (ROS). That doesn't mean
Shaymin-EX is a bad card (it's quite strong!) or that this happens to
Shaymin-EX "all the time", it just means that being forced up front (or a sniping target) for an easier KO is a legitimate concern for the card.
Shaymin-EX tends to be used up as soon as you finish drawing with Setup, barring decks that really want to bounce it.
Shaymin-EX is two fairly easy Prizes once it is up front but without some bounce its just taking up space on the Bench;
Manaphy-EX has an Ability that works so long as
Manaphy-EX remains in play, adding incentive to KO when it is useful, and when it isn't... it isn't serving a purpose.
Still even if It's low HP is slightly problematic.
Significantly "problematic", not slightly, is my prediction. Again this does not anticipate a radical shift in the metagame. Such a shift does not automatically mean different attackers, just tactics involved: if current strategy that quickly hits hard enough for a OHKO is replaced by a different strategy that quickly hits for a OHKO, it still doesn't affect
Manaphy-EX.
In standard It's still worth switching switch with Manaphy EX in order to make room.
It doesn't always make more room though. Changing something out with
Switch is
not the same as manually retreating, even for free. The reason why
Darkrai-EX or a similar effect is combined with the likes of
Keldeo-EX is because the combo allows you to replace your one permitted retreat for the turn with an effective
Switch. It doesn't often save that much space when you consider everything involved; it just allows a similar amount of space to generate more advantage.
Float Stone allows the equipped
Keldeo-EX to pull the trick all on its own and it
still is only a savings in space for decks that would otherwise have not only maxed out
Switch or another similar card, but
both.
Manaphy-EX may replace all copies of
Switch in a deck, but mostly because the deck was only running one or two
Switch (or similar) cards in the first place and doesn't have the room for both
Manaphy-EX and
Switch.
It's not that weird people are excited for this new water support.
Not worried about them being excited, I am worried about them giving a card undue hype; the two don't have to be the same thing. Hyping something unworthy is quite normal, so not "weird" unfortunately... because even though it is a regular occurrence it is not a good thing.
Ofcourse It's attack is not as good as Darkrai's. However there are some other prospects in it's favour. It can be searched with Dive Ball, it can be retrieved with Archie's Ace in the Hole and it can be healed by Rough Seas... Perhaps a bit situational. I wouldn't call It's attack bad, It's a nice last resort, two energy for 60 damage plus healing, in a defensive deck.
Uhm... I totally agree about Clemont though
And... I largely agree with what you say here. I don't see them as being as large of positives, with the attack something that might have been okay on something larger that already had a reason for being in a deck. For example, a hypothetical new attacker that had a second attack that justified running it... well then 60 for [WW] and 30 mass heal is a nice secondary attack, even if it is situational.