Man Eater Bug's effect is mandatory, it must select a target, meaning if there's no other monsters, it must select itself.
Summon Limit restricts the number of times you can Special Summon. Scapegoat summons all 4 tokens at once, so it's a one-time summoning, so your opponent can still summon one more time for that turn.
Lightning Vortex is non-targetting so it never really activated 'on' a specific monster, even if it's alone. If your opponent uses Lightning Vortex and you have an XYZ monster, that monster will be destroyed, as per usual, unless that particular XYZ can save itself from destruction with an effect.
you will not be allowed on your moshi monsters account
nothing happens. You can just get them.
Skill Drain will do the following:If a monster activates an effect, and the monster is face-up on the field when that effect resolves, then that effect will be negated.If, when the effect resolves, the monster is not face-up on the field, then the effect will resolve as normal. This happens to monsters who activate and resolve in different zones, monsters tributed for the activation of their own effect, and monsters destroyed, or flipped face-down before their effects can resolve.A monster's continuous effect will be negated until Skill Drain is removed from the field.
it will be polymerized and trishula or black rose's effect will be ineffective
Since both monsters are your opponent's weakest monsters, you get to pick which one your Fissure destroys.
If the opponent has no monsters in deck, or no monsters that Last Turn can special summon, then they just don't get a monster, nothing happens in the additional battle phase, and the opponent will probably lose in the end phase.
If the opponent's monster is in attack mode, then both monsters are destroyed. If it's in defence, then nothing happens.
What happens is you choose a monster on your opponent controls. Then you choose monsters in your graveyard to remove from play. But you have to remove monsters from play equal to the Level of your opponent's monster. Then your opponent's monster that you chose is destroyed. Eg. If you wanted to destroy Giant Rat, then you would have to remove 4 monsters in your graveyard from play because Giant Rat is Level 4.
Your Dark Magician will be destroyed, his Summoned Skull will not. Neither player will take any battle damage.
As per Soul Exchange's effect, one of the monsters for Amazoness Archer's cost can be one of the opponent's monsters.
The POST runs
Summon Limit restricts the number of times you can Special Summon. Scapegoat summons all 4 tokens at once, so it's a one-time summoning, so your opponent can still summon one more time for that turn.
Jinzo's summon will be negated, its continuous effect will never be applied.
Your opponent's Windstorm of Etaqua changes the battle positions of all face-up monsters you control, then your Creatue Swap swaps your monster and your opponent's monster, since Creature Swap's effect only says that those 2 monsters can't change their battle positions for the rest of the turn, so the position change before the swap is legit.
Lightning Vortex is non-targetting so it never really activated 'on' a specific monster, even if it's alone. If your opponent uses Lightning Vortex and you have an XYZ monster, that monster will be destroyed, as per usual, unless that particular XYZ can save itself from destruction with an effect.