The first paragraph of text is titled enrage, and reads, Whenever Vrondiss, Rage of Ancients is dealt damage, you may create a 5/4 red and green Dragon Spirit creature token with When this creature deals damage, sacrifice it. Thats not a bad ability, but it requires you to be able to damage Vrondiss here without killing them, ideally a few times per turn
For all commanders, the kind of starting hand you want generally includes at least three lands (two if you have a decent selection of mana rocks in your hand)
This will kill most attackers, it is a nice surprise EoT dork to threaten planeswalkers, it just has a good chance of doing useful things for a low cost and with a lot of versatility
Regardless of your end goal, investing in a good printing service can give you peace of mind
Tarkir is a really bad format for filler-level creatures that cost three, four, and five mana
It can be fun without any in-app purchases, it's right on your phone, and it's a snappy, modern experience