Three mana to bring a single tapped basic into play isnt a great deal, but the fact that Earthbender Ascension also makes you a 2/2 via Earthbending more than makes up for that
Now, Zirdas discount is set at two, just like Training Grounds, but Agathas ability is on a sliding scale tied to her power
In the past, this has ranged from packs to a free Limited event
2: Create two 1/1 black Nightmare creature tokens with "At the beginning of combat on your turn, if a card was put into exile this turn, put a +1/+1 counter on this creature." 7: Target player exiles the top X cards of their library, where X is the total mana value of cards you own in exile
You can also opt for strategies that involve building consistent damage over time, such as inflicting the Poison status condition