Sigma noticed that the enemies weren't trying to investigate the hole, and they waited for a while to check if any signs behind them would appear. That said, the groups on the sides began to move ahead to complete the environment. Sigma was a bit closer to the ones on the left side, but attacking them will alert all the enemies he was crunching down behind a tree covered in the carpet of grass, after all…
Still, he made up his mind because he didn't have time to waste. First of all, Sigma charged one Power Shot, and then he aimed at the group in front of the hole. When it had enough energy, he fired the arrow and caused a huge impact in front of the hole, and the blast pushed them away.