“Lava Golem” must be Special Summoned to your opponent’s side of the field using its effect text; you cannot Special Summon it or Tribute Summon it to your side of the field.
However, if Special Summoned correctly and then sent to the Graveyard, you can use “Monster Reborn” to Special Summon “Lava Golem” to your side of the field, but you (as the controller) will then take the 1000 damage during your Standby Phases.
You cannot Summon or Set and then Special Summon Lava Golem.
If you Special Summon “Lava Golem” onto your opponent’s side of the field they can activate “Bottomless Trap Hole” since you performed the Summon. You could not activate “Bottomless Trap Hole” even though the “Lava Golem” will be on their side of the field.
You can Tribute “Sheep Tokens” to Special Summon “Lava Golem” because it is not a Tribute Summon.
Since Tributed monsters are not considered to be targeted, you can use “Lava Golem” and Tribute your opponent’s Dragons even if he has “Lord of D.” on the field.
You cannot Special Summon “Lava Golem” if the opponent has “Jowgen the Spiritualist” face-up on the field, nor can you Tribute their “Jowgen the Spiritualist” to Special Summon “Lava Golem”.
Netrep Rulings:
“Lava Golem’s” condition preventing Normal Summons and Sets during the turn “Lava Golem” was Special Summoned applies even if “Lava Golem” is Special Summoned from the Graveyard.
If “Remove Brainwashing” is on the field, “Lava Golem” will change control to the owner’s side of the field.
If “Skill Drain” is active on the field, the 1000 Damage inflicted by “Lava Golem” every Standby Phase is negated. If “Skill Drain” is active on the field, the condition preventing Normal Summons and Sets the turn “Lava Golem” is Special Summoned is not negated.