Tactics
Naturally by his own beliefs, he prefers to fight with his full power as a warrior. However, due to the Command Spell of his Master Kotomine "Fight with everyone, then withdraw," he was commanded to involuntarily perform reconnaissance missions. Even in the middle of his first battle with EMIYA, he showed decisive action by leaving the battle to kill Emiya Shirou whom he recognized to have witnessed it. The withdrawal was also very skilled, giving the appearance of realizing that the situation was unfavorable. Contrary to his legendary battle prowess, Cú Chulainn's fighting in the Fifth Holy Grail War was extremely limited.

Fate/complete material III; Servants of the Fifth Holy Grail War, pg. 22-23