English (Source)
Whenever this tower kills an invader there's a <Highlight>{{ON_INVADER_KILLED:CHANCE:percent}}%</> chance to trigger a bonus attack.
Japanese Translation
このタワーが侵入者を倒すたび、<Highlight>{{ON_INVADER_KILLED:CHANCE:percent}}%</>の確率でボーナス攻撃を発動する。