[Oshizu]

Maybe just use sourcemod plugin to control their spawning etc. and make stuff like waves, amounts managed by config file example configs/zombiehorde/cp_manor_event.cfg

[Powerlord]

It may be worth checking out a decompiled version of cp_manor_event to see how the map spawns the horsemann. It may be that entity_spawn_manager only works on things derived from certain classes... it was originally added to the game to randomize pumpkin bomb spawns on koth_harvest_event. I haven't checked which classes pumpkin bomb and tf_zombie each inherit.

[friagram]

https://developer.valvesoftware.com/...v_entity_maker

https://developer.valvesoftware.com/wiki/Point_template

works with about any entity

[Requiesta]

Hm it's a thought but there's a serious problem with that method. You can't create tf_zombie entities in hammer. They are listed as npcs and every attempt I've made to create them comes up short. Thus you can't actually store them in a point_template. You can only spawn them like npcs.

[friagram]

add them to hammer's FGD manually perhaps?