in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.Railway Brawler makes later creatures arrive with a substantial boost. Whenever another creature enters under your control, the Brawler puts +1/+1 counters on it equal to that creature's power. A creature that enters as a 4/4 can become an 8/8, while creatures with higher power or other bonuses can receive even more counters.
The power is checked when the trigger resolves, so changing the new creature's power beforehand can change the counter count. Existing static bonuses also matter. Branching Evolution and similar counter support can increase the counters placed, making the Brawler attractive in green decks that already care about large creatures and permanent growth.
Plot lets you pay four mana to exile it from hand and cast it for no mana on a later turn at sorcery speed. That spreads the setup across turns and leaves more mana available for follow-up creatures on the turn the Brawler arrives. You cannot plot and use that permission to cast it on the same turn. The Brawler does not put counters on itself through its own entry, and it needs subsequent creatures to generate value. Reach and trample still provide a useful body, but a hand with no follow-ups may not exploit the main ability. Plan a turn where you establish the Brawler and then deploy another meaningful creature or token producer. The payoff is strongest when the larger bodies have evasion, trample, or another way to translate their new size into progress.
