The reason why we use the skill It's a Toon World even though we have Toon Kingdom in the deck is because we want a more consistent OTK. Having Toon World already on the field at the start of the duel means that we require one less card to set-up making the combo more consistent.
The Field Spell
Toon Kingdom is essentially the better version of Toon World. With no LP cost, it uses your cards from your deck to activate, banishing them face-down. But with only 1 copy of this card obtainable, getting it in the duel can be a problem, but once you manage to get it, your toon monsters will be invincible. Search out Toon Kingdom with Planet Pathfinder, or Toon Table of Contents.
Toon Kingdom and Toon World are key to your deck's strategy. If they are destroyed your Toon monsters follow them to the graveyard and you will be put in an unfavorable position. To prevent this from happening, protect your Toon World with Magic Reflector which puts a counter on your face-up spell card that blocks it from being destroyed. Although this does not prevent it from being banished by cards like Cosmic Cyclone.
Toon Dark Magician Girl
Some Toon monsters can be special summoned making them quicker to get out on the field, the down side is that these monster usually require you to have Toon World on the field before they can be special summoned.
Toon Dark Magician Girl is unique among Toon monsters, because she can attack immediately the turn she was special summoned. Although you are required to tribute 1 monster to special summon her.
Toon Mermaid can be special summoned, making her good tribute fodder for stronger monsters.
A powerful search card capable of getting any card with Toon in it's name out of your deck. Use this to search out anything missing from your OTK combo. Search out Toon Dark Magician Girl for your attacker, Toon Mermaid if you need tribute fodder, or Toon Rollback if you need your OTK enabler.
This card allows one of your Toon monsters to attack twice. The best target for this card is Toon Dark Magician Girl because she is the only Toon monster that can attack during the turn she is summoned. With a 2000 attack stat, she just enough attack to defeat your opponent with 2 direct attacks. Toon Summoned Skull is the next best option if you do not control a Toon Dark Magician Girl. But keep in mind he cannot attack the turn he is summoned, so do not use Toon Rollback on the same turn you summon him.
Sphere Kuriboh and Enemy Controller are excellent defense options with their own unique traits. You can use Sphere Kuriboh directly from your hand unlike other protection cards that need to be set, making them vulnerable to removal. Enemy Controller can be used to take an opponent's monster if you need to push for more damage during your OTK combo. Treacherous Trap Hole is a powerful trap card that everyone is using. It is good because by itself is to destroy 2 monsters your opponent controls for no cost. If used at the right time this could completely stop your opponent from doing anything further for that turn.
De-Spell is also good for destroying your opponent's HHG before you activate your Toon Kingdom.
Gravelstorm can be used to return your Toon Kingdom back to your hand. If it doesn't get destroyed, your toon monsters won't get destroyed, but using Toon Kingdom again will cost another 3 cards from your deck.
Toon Mermaid can be special summoned once you have Toon Kingdom/World active. This can lead to a tribute summon to get your stronger monsters right away.
Since toon monsters can't attack the turn they are summon, Soul Exchange is a really good card to use. Using it early instead of for taking down your opponent's stronger is still fine. This is because your toon monsters can't be destroyed by battle, or card effects.
Toon Dark Magician Girl can attack directly right after it's special summoned, unless you summoned using Soul Exchange.
Toon Summoned Skull has high attack, but its problem has always been its low defense. Using Toon Kingdom, your Toon Summoned Skull will not get destroyed as easily, but each attempt to attack will cost 500 LP.
There's a bunch of toon cards that haven't been released and most aren't even that broken for duel links (besides toon cyber dragon and comic hand which is the best toon support spell in my opinion). Toon mask, shadow toon, and all the other toon monsters that aren't released could be in the structure deck imo
I kinda forgot about Comic Hand, but I highly doubt we'd get it anyway. We don't even have the much weaker Falling Down or Mark of the Rose, and I don't think Konami would allow a card that steals a monster and turns it into a direct attacker. Likewise, Shadow Toon and Cannon Soldier aren't happening.
Toon Cyber Dragon crossed my mind, but I simply forgot to mention it. It's possible, though.
That's why I said comic hand was broken, the fact that it makes an opponent's monster into your own direct attacker with no lp cost that can be protected by toon kingdom would probably break the game. Not to mention that the "treated as a toon" monster would still be able to use its original effect whilst being a toon 0_0
My point was more there aren't enough acceptable Toon cards to really make a Structure worthwhile. Toon Dark Magician, Red-Eyes Toon Dragon and Toon Briefcase are the only good Toon cards we'd possibly get. (I'm not sure they'd even give us DM honestly.) Those plus like Mask, GAF and Ancient Gear Golem don't seem like they'd make for an especially good Structure.
If you use Hey, Trunade while Toon world and Toon Monsters are on the field, toon Monsters are not destroyed, right?