Alomomola is a fairly beefy Basic Water-Type Pokemon. Basics, as always, are the easiest to get into play and make space for in your deck, and even after the format change we'll still have Pokemon Collector as well as a few non-Supporter Trainers to snag them from the deck. Its 100 HP means that outside of its Weakness, it isn't an easy OHKO even for many Stage 2 Pokemon. That Weakness can be problematic with the current format and the next already having multiple, solid-to-great Lightning-Type decks. No Resistance is disappointing as always, but since it is so common it isn't going to wreck this card. The three Energy needed to retreat does hurt, and you'll be feeling it if you have to manually retreat.
Water Pulse is like the Resistance: a bit disappointing but all to common a filler attack. It isn't totally vanilla, possessing an automatic Sleep inducing effect but given how relatively weak such an effect is, TPC probably could have left it with a (CC) or even a (W) Energy cost with the 20 damage. Fortunately the second attack can get this into the right deck:Hydro Pump. Three of any Energy will let you hit the opponent for 40 points of damage, and that is... actually a bit weak by modern standards, and not especially except for the slowest formats the game has had. Of course, like all versions of Hydro Pump, that is because you get more damage from using Water Energy. There are no annoying restrictions like "up to X Energy" or "not used to pay for the attack", so if you have three Water Energy on this Pokemon, then it hits for 70. Still not so great for the current format, but pretty good for HGSS-On.
There is a pretty obvious use for this card: opener/closer for a Feraligatr Prime Rain Dance deck. As mentioned earlier, there are multiple cards to get this to the hand/field easily in both formats, and while the return isn't stupendous, in a deck that can easily drop at least three Water Energy and up to five without breaking a sweat, it'll be enough to take down a lot of Pokemon. With some forethought, it can take out almost anything (baring various effects), and since it is a Basic Pokemon you'll have room for the various supporting cards you'll need, like Energy recycling and search cards. In a Rain Dance deck it is okay if this gets OHKO'd, even while loaded with Energy, because you should have enough Energy in your deck to load up the next Pokemon while playing cards to draw into what is left and/or recycle what was lost.
In Limited play, you can use it as an okay Water splash (pardon the pun) in a non-Water deck to put out Fire Pokemon... yes, the last pun was intentional. Since the set has a decent amount of Fire Pokemon, that could be pretty important. If you have enough Water Pokemon (or a lack of anything else especially good needing specific Energy) then this becomes an even better pull, as both attacks are much improved in this format. Even just one or two Water Energy will make Hydro Pump worthwhile against any Pokemon and not just those Weak to Water.
Ratings
Modified (MD-On): 7/10, Rain Dance only
Modified (HGSS-On): 8/10, Rain Dance only
Limited: 7/10, in general
