O-Kagachi is in this weird spot where there's much better beaters at 6 mana (heck, Territorial Hellkite is a better beater at 4) and there's much better rattlesnakes at much less mana, such as Karmic Guide, Soul Snare, even Seal of Primordium
The decks also have matching Energy symbols on the deck boxes, making them easy to identify
If youre looking for something more suited to complete beginners to trading card games or children, the Disney Lorcana TCG Gateway is a simple box set for two players that is perfect for simplified learn-to-play
Going off of gacha standards, there'll probably be one or two of these cards available to pull for on a rotating basis
: The equipped monster cannot be targeted by the opponent's monster's effect
Any counters that it had on it, such as +1/+1 counters from undying, will go away (unless the permanent ordinarily enters the battlefield with counters on it, like Djinn of Wishes does)