how to unlock more heroes in Zombie Idle Defense?
Unlocking new heroes in the game is not the easiest, nor the fastest thing you can do, even though you unlock 4 slots in your team relatively fast.
Basically, you will unlock new heroes by being active and playing the game constantly. The first one you unlock is Squirrel, which joins you at stage 10 in New York. You will get Captain Redeyes after playing the game for 7 days, Big Daddy after beating the New York stage and so on.
You can also get heroes by purchasing various packs with real life money in the game – including crates that reward you Hero cards randomly.
Get that Cannon ASAP (vs Perks)
As soon as you unlock the Research function in the game, make sure to unlock the Turret – it basically acts as a brand new Hero, choosing constantly at zombies and helping you a lot.
The turret itself starts out with some pretty poor stats, but it can be upgraded as you get more research points and will become a real beast later on, having an important contribution in defeating the incoming zombie waves.
The biggest problem with the cannon is that is shares the same currency needed to but Perk cards, which are also useful, giving you massive boosts to various weapon types.
However, because of the randomness coming from Perk cards (you don’t really know what you’re getting next), I would recommend focusing early on on the Cannon and only when you have a nice amount of research points, move to investing in Perks as well.