Examples include Sword of the Meek with Thopter Foundry, Krark-Clan Ironworks with recursion triggers like Myr Retriever and Scrap Trawler, Riddlesmith with Ovalchase Daredevil, or Grand Architect with Sai, Master Thopterist
That limitation even includes simply tapping a land for mana
Even comparing Boreal Elemental against something like Air Elemental may not be that impressive, but an easy to splash 3/4 that invalidates most of the pinpoint removal would have been a notable control finisher
Remember that when we figure out what a spell costs, we start with whats written in the upper right-hand corner
Obviously, with threshold in the set, the idea was that it could be upside at times
Those tokens are way less relevant than cards like Rhystic Study, Smothering Tithe, and The One Ring