Yes
Yes if you wait a turn
The core rules state that a Normal Summon places the monster in face-up Attack position, and a Set places it in face-down Defense position. Special Summons are face-up Attack or Defense position, unless stated otherwise. If the continuous Trap card 'Light of Intervention' is active, monsters can be Normal Summoned in face-up Defense position.
Generally no, a card cannot be manually switched to face-down Defense Position after it is Summoned on the field in face-up Attack Position. There are some cards that allow you to switch it into face-down Defense Position as an EFFECT. For example: Golem Sentry.Golem SentryEARTH/Rock/Lv 4/EffectATK: 800DEF: 1800You can flip this card into face-down Defense Position once per turn. When this card is Flip Summoned successfully, return 1 monster on your opponent''s side of the field to the owner''s hand.With cards such as Golem Sentry, you can Normal Summon it and activate its effect, flipping it face-down in Defense Position, in the same turn.
Yes, if you control a monster in defense mode and it is changed to attack mode during the Battle Phase by a card effect, it can attack. The "Zero Gravity" Trap card is an example of a card that can switch your monsters' battle position during the Battle Phase. But if the monster already attacked that turn, was switched to defense mode, then changed to attack mode again by an effect, it cannot attack again on that same turn.
Face-down Defence Position refers to a monster card that is both:In Defense Position (the card is horizontal)and face-down (you can only see the card's back)
Yes, that is allowed. You cannot, however, attack and then change to defense in the same turn.
It depends.If the Monster declares an attack or already attacked and it is switched to defense position by a card effect (like Enemy Controller or Book of Moon for example) the Monster's position cannot be changed by you, the controller, because it declared an attack already. A Monster's position cannot be changed by their controller for the rest of a turn after they declared attacked with it.If the Monster did not attack yet this turn and their position is changed due to a card effect, it can be changed by the controller.
If the attacking monster is switched into Defence position, the attack ends. Damage Calculation is not entered, you do not compare the monsters' ATK or DEF.
Activate only when a “Cloudian” monster(s) you control is destroyed by its own effect and sent to the Graveyard. Special Summon 1 of those monsters from your Graveyard in Attack Position and place 1 Fog Counter on it. It cannot be changed to Defense Position by a card effect... personally I don't get it either.
No, not at all. You can attack their attack position monsters first if you want.
Yes if you wait a turn
The core rules state that a Normal Summon places the monster in face-up Attack position, and a Set places it in face-down Defense position. Special Summons are face-up Attack or Defense position, unless stated otherwise. If the continuous Trap card 'Light of Intervention' is active, monsters can be Normal Summoned in face-up Defense position.
Unless there is a card effect preventing it, it can attack.
The opposite of defense (to defend a position) is offense(to attack).
Generally no, a card cannot be manually switched to face-down Defense Position after it is Summoned on the field in face-up Attack Position. There are some cards that allow you to switch it into face-down Defense Position as an EFFECT. For example: Golem Sentry.Golem SentryEARTH/Rock/Lv 4/EffectATK: 800DEF: 1800You can flip this card into face-down Defense Position once per turn. When this card is Flip Summoned successfully, return 1 monster on your opponent''s side of the field to the owner''s hand.With cards such as Golem Sentry, you can Normal Summon it and activate its effect, flipping it face-down in Defense Position, in the same turn.
When a monster attacks a defense position monster with DEF equal to to the attacking monster's ATK, no damage is inflicted to either player's Life Points and no monsters are destroyed in battle. Some monsters have effects that activate before or after they battle, so you must take those into account as well.
You cannot tribute summon a monster in face up defense position. You can either tribute summon a monster in face down defense or face up attack position. If you want to summon in face up defense, you need to special summon.