General Strategy

• The mid-game of XMAS Nightmare leans away from hordes, instead leaning into small groups of tanky and/or fast enemies, with Wave 12 being an exception.
• Players' Focus should shift towards single-target, high DPS towers to deal with them. Such options include bottom path Juggernauts and Railgunners.
• Players are highly recommended to get backline defenses such as Barracks, as players will not have adequate DPS to deal with the wave structure's spawns; as such, enemies will almost certainly leak.

Specific Waves

• Wave 8 is one of the hardest waves in XMAS Nightmare; it contains numerous Gift Boxes, which on death spawn countless Toys. Towers that have high range and possess good crowd control capabilities, most notably Artillery, are required in order to beat this wave.
  • Players should lead their shots (aim ahead of where their target is, rather than where their target is at the present) when using the Artillery for maximum effect.
• Wave 10 marks the debut of the Super Naughty, a tanky but slow enemy. The previous wave's XMAS Walls will still be alive and tank damage for the Super Naughty to punch through. Setting towers to Strongest can help mitigate this issue.
• Wave 13 marks the debut of the Wendigo, a strong and fast enemy. Two Super Naughties, with one being stealthed, also spawn. Players should have both strong stealth detection and backline defenses in the inevitable case that they leak.
• Wave 14 has a rush of Wendigos, appearing in pairs of two. Backline defenses are critical to clean up any leaks.

General Overview

• The late game is where focus shifts to hordes of tanky enemies. Players should invest into either high DPS, single target towers (such as 2-4 Juggernauts) or towers that excel in crowd control, such as 5-2 Artilleries with their targeting set to Random.
• Do not neglect backline defenses, as the sudden shift from single target DPS to hordes of tanky enemies will require numerous high end towers to deal with and can allow faster enemies to punch through. Continue to place down and upgrade high end towers while also reinforcing the backline defenses.
• On Wave 19, the final wave, players should have several maxed DPS towers alongside more high-level ones. The Nightmare Exo Santa makes its appearance, with it being pretty much the same as its normal variant but with stronger abilities. However, the real difficulty comes from the Multiplier X that clones it later on.
  • Players should carefully manage their DPS by selling some towers as to avoid killing the Nightmare Exo Santa too early, allowing the Multiplier X to leak and end the game. Similarly, if the defenses are doing too little DPS, they should upgrade preexisting towers and use support towers' abilities.
  • When the Multiplier X inevitably clones the Nightmare Exo Santa, setting towers to Last to finish the original is highly recommended because: players will avoid having to deal with two bosses, which will almost certainly wreck havoc on the defenses, and players will not receive any more $Cash after the death of the original Nightmare Exo Santa.

Notable Waves

Notable waves besides the aforementioned include the following:

• On Wave 16, a stealth Elite Grenadier will spawn. Towers that both detect stealth and do a different damage type / ignore bullet resistance will be vital to clear the Elite Grenadier's spawns. The Shocker it spawns in particular can allow enemies to leak past the defenses while they are stunned, so backline defenses should not be neglected.
• Wave 17 marks the debut of the Multiplier 3, which can turn the tide of a battle with its Multiplication 3 ability. Furthermore, the previous wave's enemies are likely to still be alive. Killing the Multiplier 3 when it is far away from any Super Naughties is critical to survival. Such options to taking it out include using Artillery or setting a tower's targeting to Weakest.