As explained above, the original plan had been for Volrath to take the shape of Tahngarth, so we had originally planned to do one Tahngarth during Tempest block and then another one later that would subtly hint that Tahngarth had changed
At least to decide wether it makes sense in the cube or gluts up the board too much
In particular, you can use any (or all) of the additional costs of a spell with spree, another mechanic from OTJ
(Look at the top two cards of your library
For regular readers of my blog, this is a topic that comes up oftenthe tensions of legendary having rules baggage
Thinking about EDH specifically, you can maximize that -1 ability to either go heavy on tap and untap synergies, or to have your creatures untapped and ready to defend your captain