For the cost of seven mana, this Slug Horror states that at the beginning of each player's upkeep, a slime counter is put on each creature you don't control, with each creature getting -1/-1 for each slime counter on it
Versatility is the name of the game for Hide / Seek its great for removing artifacts and dealing with enchantments versus decks that are likely to recur them, and it helps you eliminate your opponents key cards in Game 2 once youve seen their deck
The reason is because you'll find yourself doing a whole lot of nothing in the early part of the game, and you'll often be dead long before you get to cast those big, powerful (and expensive) spells
Though if I need to, this is at least not too difficult to enable, so it looks like an awesome aggressive creature for red
Competitive play demand is the most stable price floor there is