Goblin Slayer was indirectly helping the other Hero party in maintaining world peace by eradicating menaces known as goblins. While the Heros eradicate gigantus monsters that crawled out straight from hell. That would also explain why Mother Earth responded to the priestess's pleas for a miracle, otherwise the entire world would have been preyed by various monsters.
So everything is connected in the end
Goblin Slayer was indirectly helping the other Hero party in maintaining world peace by eradicating menaces known as goblins. While the Heros eradicate gigantus monsters that crawled out straight from hell. That would also explain why Mother Earth responded to the priestess's pleas for a miracle, otherwise the entire world would have been preyed by various monsters.