Lavakin Brawler — ruling 1

The size of the bonus is determined as Lavakin Brawler’s ability begins to resolve; it won’t change later in the turn if the number of Elementals you control changes.

Lavakin Brawler — ruling 2

Because Lavakin Brawler is itself an Elemental, its ability will usually give it at least +1/+0.

Lavakin Brawler : règles, fonctionnement et interactions (MTG)

Lavakin Brawler is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Whenever this creature attacks, it gets +1/+0 until end of turn for each Elemental you control.

How it works : Lavakin Brawler

Original English text — Wizards of the Coast / Scryfall

#1July 12, 2019· Wizards of the Coast
The size of the bonus is determined as Lavakin Brawler’s ability begins to resolve; it won’t change later in the turn if the number of Elementals you control changes.
No other card is named in this ruling.
#2July 12, 2019· Wizards of the Coast
Because Lavakin Brawler is itself an Elemental, its ability will usually give it at least +1/+0.
No other card is named in this ruling.