First strike Boast abilities you activate cost {1} less to activate for each Dragon you control. Boast — {4}{R}: Create a 5/5 red Dragon creature token with flying.
2021-02-05
Once you announce that you're activating a boast ability, no player may take actions until the ability has been paid for. Notably, opponents can't try to change the activation cost by removing your Dragons.
2021-02-05
The cost reduction applies only to generic mana in the activation costs of boast abilities you activate. It can't reduce requirements of specific colors of mana.