Yeah, obviously a creature with Haste or Trample or whatever is very easy to make a simple parser for. But I can imagine because WotC is so strict on how they word text on cards, even more advanced interactions would be pretty straight-forward to parse. Like, if a card says:
"When <card name> enters the battlefield, return target non-land card from your graveyard to your hand".
Both parts of that sentence is always worded the same, so it's probably quite straight-forward to make a parser for this: just have a parse rule for "When <card name> enters the battlefield, <triggered ability X>", with a database of triggered abilities (and their implementation) that include all the ones that have already been printed.
