OrCost

[Titania, Rugged Rumbler](https://scryfall.com/card/msh/235/titania-rugged-rumbler) has complex Ward cost that is A or B.

> Ward—Discard a card or pay {2}. (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player discards a card or pays {2}.)

An **easy** way would be to make Ward support two different costs via generic Choice,
but `Ward:CostA:CostB` is already used as `Ward:Cost:Desc`, so that might not work.
See "[Minthara, Merciless Soul](https://scryfall.com/card/clb/286/minthara-merciless-soul)"
>`K:Ward:X:where X is the number of experience counters you have`

A **better** handle this would be that we need a Cost like `Or/2>`
That would help us with other places too.