Game Concept - Tide

I want to explain the concept of Tide and how my game fits into it.

Shout out to one of my friends who made this game https://itsjimmy.itch.io/1-wizard-army

It brought forth a few design questions into my mind, given that he had asked me for feedback on it. Concepts like tide, loot rarity and loot power and so on. The Void's Gaze was largely based around ideas I learned by playing his game and Vampire Survivors.

First I want to describe the concept of Tide.  
Before we get into it, this is probably a decent precursor.

tl;dw constant adrenaline = bad, no adrenaline = bad

The concept of tide in a tower defense game, or any vampire survivor esque game, can be defined as how close to losing you are at any given moment. If I'm constantly 1 mistake away from losing, and that's the entire game loop, the game won't be very good. If I'm waiting at the enemy's spawn and instantly blasting the wave, the design isn't very good. Either one MAY appeal to a niche group, but a balance of both will appeal to a much larger audience.
Tide can be further split into 2 parts, tidal position, and tidal pressure.

In Vampire Survivors, tide can be ROUGHLY measured by how far away the horde is from your character. If they're touching your character, the tidal position is maxed, if they're dying at the edge of your screen, the tidal position is at the minimum.

In 1 Wizard Army, and Void's Gaze, tidal position can be defined by the horde's distance to the castle.

If the tidal pressure is a constant negative, the player will have to routinely take a step back every time a new wave spawns, like clockwork, until the castle is being attacked, and the tidal pressure can be measured by how far the character needs to step back.

If the tidal pressure is a constant positive, the player takes a step forward every time a wave spawns, until the player is erasing all enemies on spawn.

The key to making a tide based game good,  is having variance in the tide.
For example, I might want the first 4 waves to have a slightly negative tidal pressure, so that the player ends up halfway across the field, then have the 5th wave  spawn with a boss that pushes the player to a quarter field away from the castle. Then the next 4 waves have a slightly positive tidal pressure, so the player can regain field to maybe three quarters.

Tide should be looked at as a resource that is managed by the designer and mitigated by the player.

Here is how my game, The Void's Gaze, utilizes Tide.

In Void's Gaze, given it was made in two  weeks, there's 2 major tide phases.

In the first major tidal phase, where only skeletons and deer spawn, the player initially has an extreme positive tide, where they can get a few levels without worrying about anything. As each minor wave spawns, the tidal pressure slowly shifts negative, until the backend of the major tide phase, where the player is nearly guaranteed to lose some castle health.

In the second major tidal phase, each subwave doesn't spawn until the previous one has been fully cleared, so the tidal position is reset every wave. BUT each subwave has massive tidal pressure, in which if the player isn't careful, the castle will lose health. As the player becomes powerful enough to handle those major tidal waves with ease, tough player hunting mini-bosses spawn and hunt the player down while ignoring the castle, adding a new dynamic for the final phase of game.

In Conclusion,
If instantly blasting the wave on spawn is a possibility in your game, it should be HARD EARNED and fleeting. If it's constantly unavoidable, you might want to add a boss or other artificial difficulty layer to that point in time. If your character is CONSTANTLY on the verge of death, you might want to add artificial ways to give them some breathing space, like the cross necklace and stopwatch in Vampire Survivors.