yeah dont pay any attention to rikko he's trolling, and does not know how to make an arguement to save his life, his oppinions are extremely biased and he does not back up his comments with facts, simply his biased opinion.
Well as for decklists this is the one i use keep in mind its a fun deck:
pokemon (18)
3 arceus lv x (omniscient arceus)
3 normal arceus
2 fighting arceus
2 dark arceus
2 psychic arceus
2 fire arceus
1 water arceus
1 grass arceus
1 steel arceus
1 lightning arceus
trainers/supporters/stadiums
4 pokedex
4 beggining door
4 pokemon collector
3 ultimate zone
3 warp point
3 proffesor oak's new theory
2 expert belt
2 copycat
1 looker's investigation
Energy (16)
4 double colorless
4 rainbow
2 dark
2 fighting
2 psychic
2 fire
Pokemon: I started off with 3 normal arceus because he is without a doubt the most helpful arceus of all between ripple swell and sky spear to knock out key threats on the bench then i added two arceus each of the ones that are gonna be ur "main attackers" dark(1D and 1C for 80 is real good) fire(next strongest attacker) fighting (1F and 2C for 60 is ur next best option) and psychic(hitting for 40 isnt the best bet but automatic confusion is a plus). Finally theres the all star of the deck omniscient arceus great hp, and good pokebodies that allow for two things one is to make one of the relatively useless arceus(ie grass and lightning) useful by using them as the base for level up and attack for weakness, and two he allows for using a multitude of attacks, wether it be getting past mewtwo lv x with the water arceus's attack or preventing damage from any level x using the metal arceus's attack it always provides a way out.
trainers/supporters/stadiums: 4 pokedex is awesome it lets u burn through ur deck and get exactly what you need, i went with 4 beggining door and no pokemon communication, bebe's search or luxury ball y? in this deck its simply better than all of those for one, you dont have to put a card back in your deck to search for a pokemon beacuase all pokemon in this deck are arceus and two its superior to luxury ball because with beggining door u can search for a lvl x. The 4 collector are a must to help you ripple swell by turn 1. In testing i decided to go with 3 ultimate zone between all the pokedex, copycat, proofesor oaks, and looker's your bound to draw it when you need it. The last two cards are expert belt and warp point expert belt is needed just in case you are not hitting for weakness, and warp pojnt is there to force the switch for your apponent or just in case you need to switch your own arceus since all arcues have a hefty 1 or 2 retreat cost.
Energy: Now i know some people might say 16 can lead to dead draws but if you put it into perspective you realize than once you have ripple swelled there's only about 8-10 energy cards left in the deck since most of the time 1 or 2 energy cards will be prized. And i only chose to run two energy cards of each of the "main attackers" energy type for obvious reasons so that you may use the main attacks without having to rely on rainbow energies.
Hope this helps get the arceus deck into perspecive
and good luck at battle roads!