Thunderclap Drake

If the spell that's copied divides damage or distributes counters among a number of targets, the division and number of targets can't be changed.

The last sentence of Thunderclap Drake's rules text was inadvertently omitted from the card. Its Oracle text has been updated to include that sentence.

Thunderclap Drake's second ability can't reduce the amount of colored mana you pay for a spell. It reduces only the generic mana component of that spell's cost.

If you have multiple commanders, you'll copy the next instant or sorcery spell you cast this turn for each time you've cast either of them. For example, if you've cast one commander once and one twice, you'll copy that spell three times.

You can't choose to pay any additional costs for the copies. However, effects based on any additional costs that were paid for the original spell are copied as though those same costs were paid for the copies too.

The copies made by Thunderclap Drake's delayed triggered ability are created on the stack, so they're not "cast."