I've been playing for years, and I think I know the game pretty well now.
I'll agree that many cards can be beneficial, particularly in the right situation. However, the strongest 1 Tribute monster around has 2800 ATK, and that requires discarding your hand plus Tributing a strong monster in order to Summon (not to mention it can then lose quite a bit of ATK because of its effect). Then there's 2600 ATK for the next strongest.
In comparison, your card has 5000 ATK, with no drawbacks whatsoever. The "send your Deck to the Graveyard" effect is optional, and quite likely most people won't use it. It's incredibly overpowered all by itself. At least when other cards manage to be that strong (either ATK-wise or a good effect), it costs a lot of resources.
Like your example, Blue-Eyes Ultimate Dragon. Requires 3 specific monsters, plus Polymerization (or another Fusion card). Quite a restriction, I think. Other monsters that are similarly strong have similarly high costs to get them out (fusing several monsters, Tributing several monsters, things like that). But your card can be brought out with 1 Tribute (in the right situation, naturally), is way too strong for the price you pay, and while its effect empties your Deck, you can very easily not use it. When you've got 5000 ATK in one place, you're going to be dominating anyway, so that effect isn't much help.
I would suggest you need to Tribute at least 3 monsters (keep the "Tribute all monsters you control" bit), weaken the card slightly, and perhaps put in another cost too (like sending the top 10 cards of your Deck to the Graveyard when you Summon it). Restrictive, yes, but then it's balanced.
I'll agree that many cards can be beneficial, particularly in the right situation. However, the strongest 1 Tribute monster around has 2800 ATK, and that requires discarding your hand plus Tributing a strong monster in order to Summon (not to mention it can then lose quite a bit of ATK because of its effect). Then there's 2600 ATK for the next strongest.
In comparison, your card has 5000 ATK, with no drawbacks whatsoever. The "send your Deck to the Graveyard" effect is optional, and quite likely most people won't use it. It's incredibly overpowered all by itself. At least when other cards manage to be that strong (either ATK-wise or a good effect), it costs a lot of resources.
Like your example, Blue-Eyes Ultimate Dragon. Requires 3 specific monsters, plus Polymerization (or another Fusion card). Quite a restriction, I think. Other monsters that are similarly strong have similarly high costs to get them out (fusing several monsters, Tributing several monsters, things like that). But your card can be brought out with 1 Tribute (in the right situation, naturally), is way too strong for the price you pay, and while its effect empties your Deck, you can very easily not use it. When you've got 5000 ATK in one place, you're going to be dominating anyway, so that effect isn't much help.
I would suggest you need to Tribute at least 3 monsters (keep the "Tribute all monsters you control" bit), weaken the card slightly, and perhaps put in another cost too (like sending the top 10 cards of your Deck to the Graveyard when you Summon it). Restrictive, yes, but then it's balanced.