Snake

The Tooth Collectors (or "Snakes") are the only DoT (damage over time) unit in the game. With each attack against an opponent unit, they add a stack of venomic acid that drains their target for 2 hp every second (this includes flying units as well). This poison lasts until that unit's natural healing kicks in, that is to say, units will remain poisoned until they are out of combat and back in their own territory. However, with many engagements taking place outside of friendly territory, being tagged by Snake poison is often lethal.

Strategy
For a single poison stack, snakes will do a guaranteed 10 damage over 5 seconds to any unit before natural healing can kick in. This makes them ideal for hit and run tactics or for adding a death timer on multiple units on the battlefield. The added benefit of being able to hit ground and air units makes snakes a well rounded addition to your unit composition.

Playing with snakes
As mentioned before there are two main ways to play snakes. The first of which is to utilize their hit-and-run tactic. Snakes don't need to be around to constantly to deal damage unlike most other units. They can tag a unit and then run, letting the poison run its course. In a straight fight, snakes can serve two roles; they can either blanket their poison to as much units as possible (particularly Tier-1 units, as it guarantees a kill eventually) or they can focus down high hp value like other Tier-2 units, boar, badger, etc. Snakes are strong on defense as opponent units have to travel back to their territory to cleanse the poison, often succumbing to the poison while retreating.

Playing against snakes
When you're being harassed by snakes, putting up some sniper balloons or barbed wire is usually good enough to prevent further harassment though you need to be careful while they are still building. Alternatively, if you have lizards, you can try to chase down any retreating snakes and pick them off if possible. In a battle, snakes are a pretty high priority target, as leaving them alone for very long can cause a lot of damage to your army. You generally want your Tier-1 units to take as many snake hits as possible. Each stack of poison does a minimum of 10 damage, so any extra stacks of poison on a Tier-1 unit (except moles) is "wasted" to kill the unit faster. Probably the safest unit to bring with you against snakes is pigeons, It takes two pigeons per poison stack to bring the net damage to zero, but it's still extending the life of an otherwise dead comrade. Keep in mind that pigeons cannot remove poison but only prevent the unit from dying from it (granted you have enough of them) by healing the damage done, you still need to go back to base to cleanse the poison without waiting for it to wear off naturally. Come late game, it's also possible to take them out before they get a chance to do anything with the fox, or to have them poison undead mice from the owl.

Changelog

 * Pre-Alpha 25:
 * Are now 35 DEF, up from 30
 * Now stops moving for .25 seconds upon firing their weapon
 * Pre-Alpha 24.01:
 * Snake poison will now be removed if a unit or commander begins to passively heal, having not taken damage for 5 consecutive seconds
 * You will now get an alert that you are under attack if a Snake applies poison off screen
 * Pre-Alpha 23.01:
 * Venom now does 2 ATK per second, up from 1
 * Venom now lasts 10 seconds, down from 15
 * Pre-Alpha 23:
 * No longer has basic attack damage
 * Damage indicated reflects damage of venom
 * Venom can stack
 * Venom now lasts 15 seconds, down from 30
 * Pre-Alpha 17:
 * Poison now affects structures
 * Pre-Alpha 12:
 * Hitpoints now 30 (was 25)
 * Pre-Alpha 11:
 * This patch changed the “damage per 5 seconds” system to a “damage per second” system.Therefore, damage values have to be divided by 5 before they are comparable.
 * Cooldown now 1 second (was 2.5s)
 * Pre-Alpha 10:
 * Hitpoints now 30 (was 25)
 * Pre-Alpha 6:
 * Hitpoints now 30 (was 25)
 * Can now attack commanders
 * Pre-Alpha 4:
 * Hitpoints now 25 (was 20)
 * Can target flying units now
 * Poison now deals 3 DMG/s for 10 seconds instead of 1 DMG/s for 30 seconds
 * Pre-Alpha 3:
 * Now do a standard attack in addition to applying poison
 * Damage now 10 (was 30)
 * Hitpoints now 30 (was 50)
 * Poison no longer stacks
 * Attack range now 4
 * Cooldown now 2.5s
 * Pre-Alpha 1:
 * Poison now deals 1 DMG/s for 30 seconds instead of 0.5 DMG/s.