A [+1] cost on a loyalty ability, for example, effectively has a cost of "increase enchanted creature's toughness by 1," though it still counts as a loyalty ability
Interaction again becomes a sticking point here, with the Committee noting that The Fantasticar requires very specific answers, whose effectiveness is often significantly reduced in other matchups, and games are often decided based on whether or not the non-Fantasticar player has said answers rather than any strategic choices made by either player
Together, these features make the card far rarer and more valuable than Unlimited or Base Set 2 versions
I don't think Twilight's Call is a good card for you
Agatha allows you to pay X less for your activated abilities of creatures you control, where X is its power
RED Red is a pretty tough slot to fill at mythic generally speaking and the default here is some combination of a planeswalker and a dragon