One should consider with great trepidation whether or not to create a card that combos explicitly (or implicitly) with itself (and I think doubly-so if it costs less than $5, as $5 cards are at least expensive enough to already require another plan), and should almost certainly explore any fashion in which the idea can be more Kingdom dependent. The more mono-card strategies that exist, the greater the chance that a Kingdom devolves into a race for a single pile. Designers should work to minimize such an un-fun game state.
Yes, this was my thinking. I think this is okay because the card doesn't combo explicitly with itself per se, rather allowing other terminals to chain with themselves, costs $6, and suspends cards outside of your hand, which prevents them from playing each other (i.e., setting aside 4 King's Courts and then playing them with Memorial will prevent them from playing each other -- they need to target other cards in your hand.)
Fly-Eagles-Fly, I don't think it's QUITE a solution for me to say "I'll post the rulebook snippet", since it wouldn't be right to make a card with gibberish and a rulebook entry to explain how to use it in a different way. What do you think the card is support to do?
The short version is, after drawing 2 cards, either play all of the copies of a single Action from your hand, or set them aside. Then, play any number of the same Action that were set aside (including ones set aside from this Memorials, or from previous Memorials, whether on this turn or previous turns).
So, example one, my hand is 2 smithies, 1 Memorial, some other cards; I play Memorial, I name Smithy, I play Smithy + Smithy.
Example two, my hand is 2 smithies, 1 Memorial, etc; I play Memorial, I name Smithy, I set the Smithies aside. A few turns later, my hand is junk and Memorial, I play Memorial, I name Smithy, I play those two Smithies I set aside last time.
Example three is the same, except I have two Smithies set aside and two in my hand. I play Memorial, I name Smithy, I play 4 Smithies!
There's some extra complications, in that, you have to play or set aside all of the copies, you can't have 3 Smithies and then play one and set aside two. It's all or nothing. Likewise, if you choose to play Smithies from being set aside, you have to play all of them. You can't keep some set aside and play a few.
Additionally, you can have multiple different piles of set aside cards; you could set 3 Smithies aside, and 2 Native Villages, and 2 Witches. But you can only name one card for BOTH setting aside and playing, so each Memorial will only access one set of "Memories."
Also as I mentioned before, the cards you set aside aren't in your hand, so they don't have as much ability to interact with each other.