There's a few different knockdown animations.
["strike_fall_back_rise", acf_align_with_ground|acf_enforce_lowerbody, amf_priority_reload|amf_priority_mount|amf_priority_equip|amf_priority_rear|amf_priority_striked|amf_priority_fall_from_horse|amf_priority_die|amf_accurate_body|amf_play|amf_restart,
[1.7, "anim_human", 45400, 45453, arf_blend_in_2|arf_make_custom_sound, pack2f(0, 0.4), (0, 0, 0), 0.5],
],
["strike_fall_back_rise_upper", acf_align_with_ground, amf_priority_reload|amf_priority_mount|amf_priority_equip|amf_priority_rear|amf_priority_striked|amf_priority_fall_from_horse|amf_priority_die|amf_accurate_body|amf_play|amf_restart,
[1.44, "anim_human", 45400, 45445, arf_blend_in_2],
["chamberkick_knockdown", acf_align_with_ground|acf_enforce_lowerbody, amf_priority_reload|amf_priority_mount|amf_priority_equip|amf_priority_rear|amf_priority_striked|amf_priority_fall_from_horse|amf_priority_die|amf_accurate_body|amf_play|amf_restart,
[2, "anim_human", 45400, 45453, arf_blend_in_2|arf_make_custom_sound, pack2f(0, 0.4), (0, 0, 0), 0.5],