spearhead
spear + head
https://gyazo.com/91155bdccdf3a88812d37b6507dcb39c
source: [fateのランサーが槍を突き刺してくるGIF画像｜無料GIF画像検索 GIFMAGAZINE 59842]
noun
the point of a spear.
やりの穂先
an individual or group chosen to lead an attack or movement:
〖通例単数形で〗(攻撃などの)先鋒（せんぽう）; (事業などの)率先者.
e.g. she became the spearhead of a health education program.
verb with object
lead (an attack or movement):
〈攻撃･事業･運動など〉の先頭, 陣頭に立つ
e.g. he's spearheading a campaign to reduce the number of accidents at work.