Generally, you may access the monsters in your Extra Deck at any point during your Main Phase and may Summon using the appropriate Summoning method, assuming you can do so
Only one deck is really a hassle to play against in my opinion, and thats Evilswarms
You can play either single-player, known in game as Solo Mode , where you proceed through a story of the cards involved playing against a computer opponent
If your opponent activates a monster effect in their hand, GY, or banishment (except during the Damage Step): You can Special Summon this card from your GY (if it was there when they activated) or hand (even if not), but destroy it during the End Phase
video games, this one comes with some special promo cards
The equipped monster's effect, "Trap Cards, and their effects on the field, cannot be activated