In many games there are effects that are directly affect the game position and aren't really comprehensible outside of it; I call these regular effects. There are often also effects that are a little more abstract in nature and are often shared between games; I call these meta effects. Some examples from my game Dot:
Regular Effect: Artist: Rotate a red Tile to a new orientation.
Meta Effect: General: Take an extra turn after this one.
Meta effects can be fun but they often generate lots of problems. A good example is early Magic: The Gathering where effects like Time Walk (take another turn) and Ancestral Recall (draw three cards) dominated the game and eventually had to be removed to preserve any semblance of balance. Ziggyny talked about a similar issue in the Campaign Manager game he played where you could build an 'infinite deck' using these meta effects and utterly dominate any deck trying to use regular effects. I remember the CCG Rage having this issue too since you were generally supposed to fight using a five card hand but there was one card that allowed you to draw ~eight extra cards and made you more powerful to boot! You know there are likely to be problems any time certain cards let you do multiple things or read "Draw three cards". I am currently evaluating two meta effects for Dot. The original incarnations are as follows:
Inventor: Shuffle your hand and reserve pile together and draw a new hand.
Spy: Opponent plays with their hand revealed until your next turn.
These presented problems. The first was that Inventor made you shuffle. I have always hated the requirement to do a properly randomized shuffle in the middle of a game and I can't imagine anybody thinks that is good design. In a computer game this effect would be completely fine; it is useful to cycle away cards you don't want right at the moment and computers can shuffle instantly. In a physical tile game though it seems poor because the interestingness of the effect does not justify the annoyance. Spy was reasonable but seemed not compelling enough and I wanted it to do more. The second iteration had a rules change which caused you to draw up to three Tiles in hand on your turn instead of always drawing one.
Inventor: Draw three Tiles.
Spy: Look at opponent's hand and force them to discard Tiles of your choice until they have two Tiles or less.
The Inventor in this iteration was good because you got greater selection for a few turns but it would certainly make it complicated to make decisions when you had five Tiles to choose from. Playing the Spy right after your opponent had used Inventor was utterly brutal though because it gave you even more selection to pin them with the worst Tiles! The other issue is this version of Spy causes a reshuffle, which hasn't magically become 'not crap' in the past paragraph. The current working effects:
Inventor: Your opponent may rotate this Tile to a new orientation.
Spy: Look at opponent's hand and choose a Tile. They may not play that Tile until your next turn.
Of course this version of Inventor doesn't sound much like an Inventor and isn't really a meta effect any more. Maybe he needs to be named Turncoat instead. He has swapped from being a relatively weird effect to a powerful bonus to a significant penalty. Quite the journey.