Yes. To Special Summon a Level 7 Toon Monster, you must Tribute any two monsters on your side of the field. For Levels 5-6, you must Tribute one. For Levels 7 and above, you must Tribute two. High Level Toon Monsters follow the same guidelines as Tribute Summons. Note that it is considered a Special Summon, not a Tribute Summon.
In the Yu-Gi-Oh rule book it states that an 8 star monster only needs 2 tributes.
As per the basic rulebook, you need two tributes for monsters of Lv7+. Some high level monsters have rules text to say they require three tributes, but these are exceptions. In the case of monsters like Yubel (Lv10) they still only require two tributes.
Assuming the monster doesn't have any special text which explains how to summon it, then a 10 star monster just requires two tributes, because Lv7+ monsters need two. The Earthbound Immortals and Andro Sphinx/Sphinx Teleia are Lv10 monsters that are tribute summoned as normal with just two tributes.
You need one tribute for a Lv5 or 6 monster, and two tributes for Lv7+, though many higher level monsters have additional or different requirements.
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No, because Tribute Summon is treated as a Normal Summon. Monsters that require tribute for a special summon (Toon monsters, Destiny Hero Plasma) are still Special Summons, not Tribute Summons.
Well, you look at what the monster's lv is (count the stars), then if it's a lv 5 or 6, then you need to send 1 monster from your side of the field to the graveyard to tribute summon it. If it's 7 or more, then it's 2 monsters. Some of them can't be tribute summoned at all, and need certain conditions to be summoned. Just remember that a tribute summon is a normal summon.
You need to tribute one monster for the tribute summon of a Lv5 or 6 monster, and two tributes for any that are Lv7 or higher, even Lv10 ones like Yubel. Additionally, some monsters require three tributes (Obelisk the Tormentor, for example), but that is stated on the card, and it not related to the level.
It depends on the level. If it is 4 stars or under, then no. If it is 5-6 stars, then you need to tribute 1 monster. If it is 7-12 stars, you need to tribute 2 monsters. Many high level monsters cannot be tribute summoned though and will have their own summoning text.
Not a lot, really. Normally a Lv5+ monster will need one or two tributes, depending on actual level, and this is called a Tribute Summon, which is still just a regular Normal Summon. However some cards let you ignore that, like Blackwing - Sirocco the Dawn can under some circumstances be Normal Summoned without tribute. Basically a Normal Summon is a Normal Summon, whether it required tribute or not.
you have to have a tuner monster on the field or the tuner monster it says you need on the synchro monster card and another monster (not a tuner) that when you add the stars from the tuner and non-tuner add up and equal the same number of stars on the synchro monster. Then you send those cards to the graveyard and special summon the synchro monster from where you fusion monsters should be
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.