Overall, that moveset for Blissey could be far better. Building an entire moveset around SolarBeam when Blissey doesn't get STAB on it and has somewhat poor Sp.Attack is just pointless, and does not make the most of Blissey's abilities at all.
Blissey @ Leftovers
Natural Cure
Bold/Calm
- Seismic Toss
- Softboiled
- Ice Beam
- Aromatherapy/Thunder Wave
Seismic Toss is by far Blissey's best way to dish out damage, since it deals out the same damage to everything you use it on. Ice Beam is there as a means of dealing with Ghost-types, since they will suffer 0 damage from Seismic Toss. Softboiled is mandatory on any Blissey set really, and the final move is down to personal preference between the two, whether you want to disable opponents or support your team. Helping Hand, even in a double battle, isn't a particularly great move considering a Seismic Toss and a second attack can usually inflict severe damage on a lot, if it doesn't outright kill the target off.
Nidoqueen is better off with Black Sludge over Shell Bell, since Shell Bell is quite unreliable when it comes to healing. Also, swap Toxic for something else - typically Toxic isn't that useful unless put on a moveset built around its use, and it shouldn't be used as a random filler move.
Finally, Dream Eater is a bad move to have on Gardevoir thanks to the nerf to Hypnosis's accuracy as well as the ever-present Sleep Clause. Psychic is the STAB move of choice on Gardevoir in every situation.
As for Attract, it isn't a very common move to see at all since its reliability is very poor overall - it only works on opposite gender Pokemon for one thing. It never works on anything that has no gender, and its effects can be neutralized by switching out. Although someone could easily lock you down by laying down Spikes/Stealth Rock and then Attract-phazing everything that you send out, the odds of this happening are very rare and even if it does, you don't necessarily HAVE to switch out upon being Attracted.
