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.
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.
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.
3SD can run Barrel Dragon (only 50% but still) or Endymion, Blue Eyes/3SD DM runs Vigilance (not backrow removal but kills TK) Hammer Shark runs Lost Blue Breaker/Fish Charge, and every Last Gamble, Handless Balance, and Bluff Trap deck runs Storm. The only meta decks that don't run something that can destroy TK atm are GK and Relinquished (which is usually used with Harpies anyways these days).