It's really bad for your mana and a tiny bit of lifegain doesn't offset that
For example, the firebending ability will count experience counters that you got from the last ability, from another ability, from another copy of Zuko, Firebending Master, and so on
If he survives a turn, a single Prince John Greediest of All solidifies a lead
In reality, the effectiveness of this strategy is a confluence of many factors, with availability of mana-fixing being one of the least impactful
Rocket's Articuno is slightly easier to find than the next few cards coming up, contributing to its slightly lower market price
if not, you're paying for the thrill of opening rather than investment potential