There aren't actually that many cards under each color trio, and many of them are simply legends
The way challenging works is a ready (untapped) character exerts and chooses an opposing exerted character to challenge, and then both cards compare their strength (attack) and willpower (defense) values to each other (meaning the attacker automatically gets hit back by the defender)
This one is Zurgo, Thunders Decree, and while he also comes with a mobilize mechanic, sitting at 2 instead of 1, it's the second ability tacked on to him that makes him such a good addition
If the creature with offspring leaves the battlefield before the triggered ability resolves, you will still create the token
What are some of the best colorless and artifact card draw options for red in MTG
They run in the same circles, so to speak