For cards like Garbage Grabber that specify 'recycle 3', do you need to target exactly 3 to recycle? And why can you play Chemtech Enforcer with an empty hand but can't recycle less than 3 cards?

Ruling: You must recycle exactly 3 cards to activate Garbage Grabber's ability because it is a cost. You can play Chemtech Enforcer with an empty hand because the discard is an on-play effect, not a cost.

Nuances:

• Costs (like recycle 3) must be paid in full to activate an ability
• On-play effects happen after the unit has already resolved and hit the board, so they attempt to resolve even if they cannot be fully completed
• On-play effects are not the same as on-cast effects