Crobat Mew Donphan Chandelure - The2TCG

3-1-3 chandelure
1 victini
2-2 donphan prime
3-1-3 crobat prime
4 Mew prime

Pokemon = 23

4 twins
2 switch
3 PONT
4 Rare candy
1 super rod
3 communication
2 collector
2 Max potion
3 catcher

T/S/S = 24

10 psychic
3 rainbow energy 

Energy = 13

Strategy

This deck relies on the low energy costing crobat prime to heavy poison your opponent, as well as snipe the bench.  Mew prime allows you to see of a pokemon into the lost zone, then use it's attacks as your own.  Donphan is to counter all of the lightning decks in format since it's easy to set up and can KO almost anything with just its first attack.  Chandelure allows you to place damage counters, similar to crobat, but as an ability, leaving you free to attack for more damage.  

Pokemon Analysis

Two stage 2 pokemon are going to be difficult to set up, even with rare candy.  Mew is a great idea to fix that problem, but it just doesn't have the HP to withstand many attacks.  It seems like you've added two decks together that don't really belong together.  Mew decks typically work with vileplume to slow down their opponent, and use a variety of different pokemon in the lost zone like jumpluff, muk and the fire chandelure.  It can also work off of prism energy. If you decide to go with this deck, you'll need 4 mew, 1-2 jumpluff, 2 muk, 1-2 donphan and 1-2 fire chandelure.  If you run vileplume with it, you won't want to run donphan on the bench since it's such a heavy retreater. Instead, try yanmega.  A psychic chandelure deck is much different and much more expensive since you need tropical beach stadiums which are $80+ each.  I'm going to review the rest of the deck as if it were a Mew deck as I've described.  The vileplume line should be 3-1-2 with 1 pichu and 1 cleffa.

Energy Analysis

4 prism will let mew use any of the pokemon attacks that it wants.  I'd recommend around 13 energy in the deck, so I'd add in 4 rainbow and 5 psychic.  You could also split that basic psychic up to include other basic energy depending on what you decided to focus on.  For example, if you wanted to put more donphan in the lost zone, then adding a few basic fighting might work better.

Trainer/Supporter Analysis

With vileplume decks the only trainers you'd play would be 3 candy and 3 communication.  The rest would be supporters like 4 twins, 4 collector, 3 judge and 3 copycat. If you have anymore room in the deck, look into adding PONT, juniper and cheren.

Overall

You asked for a deck review before going to buy the cards.  This is an excellent idea.  If you haven't already, I'd try playtesting with proxies (fake cards), that will show you how well the deck works and let you tweak it before you buy. Let me know if you need help with certain cards since most of this deck I have for sale and can give you a better deal than many popular websites.