You need to discard your hand, but if you discard Ojamagic or "Ojama" cards that can activate GY, I think you'll be fine
Now that we've cleared that up, it's time to take a look at whom these new Commander precons are designed for, and whether they might be worth picking up even if you've got some MTG experience
Crunch 'em!" When Anna activates that monster's Quick Effect, she announces "I activate Anger Knuckle's effect!" When Anna activates that monster's Ignition Effect, she announces "Anger Knuckle's effect activates from my Graveyard!" When Anna Summons, "Heavy Armored Train Ironwolf", she chants "This impregnable fortress is the terror of the railways
Its really a matter of planning your moves carefully, and knowing how to play the deck well
Add secondary Pokmon only when they directly support that plan
Same for the super rares, the metagame's best decks typically base their key synergies around those cards, and finding them on time during a match is a big difference maker