Second Wave (EU2012)

Second Wave is a game mode enabled with the fourth patch released for XCOM: Enemy Unknown. Second Wave was initially unavailable to most players, but was partially accessible to modders who unlocked it manually through manipulation of the game's code. The developers subsequently prepared the full content for release with the help of modders who had discovered how to activate it and who had tested its features, according to Jake Solomon.

Second Wave adds advanced gameplay options to increase the difficulty and randomness of the game, described below. The options are unlocked as the player wins on advanced difficulty levels.

Starting Options

• Damage Roulette - Weapons have a much wider range of damage
  • Does not apply to explosives.
  • Damage range is doubled, i.e. an Assault Rifle with a 3 damage stat can deal up to 1-6 normal damage or 1-9 critical.
• New Economy - The funding offered by individual council members is randomized.
• Not Created Equally - Rookies will have random starting stats.
  • Range of Aim: 55~80. (normally 65), Range of Movement: 11~13 (normally 12), Range of Will: 25~60 (normally 40)
• Hidden Potential - As a soldier is promoted, their stats will increase randomly.
  • HP gain is randomized too. Soldier may gain HP at a rank they normally don't, or don't gain any when they normally would.

Unlocked after winning on Normal or higher difficulty

• Red Fog - Any wounds taken in combat will degrade a soldier's stats for that mission.
  • -15 aim with light wound, -30 with heavy wound.
  • Even 1 point of damage is considered as light wound, even though that HP is from armor.
  • Movement is impaired by wound too.
  • Debuff is not cured with Medikit heal.
• Absolutely Critical - A flanking shot will guarantee a critical hit.
  • Shots to flanked or exposed target has +100% crit chance, rather than +50%.
  • Hardened target has -100% chance to hit by critical, rather than -60%.
    • So it negates +100% from exposed penalty, but still 10% higher chance to be critically hit than normal. (where they has 60% - 50% = 10% resistance to crits.)
• The Greater Good - The secret of psionics can only be learned by interrogating a psionic alien.
• Marathon - The game takes considerably longer to complete.
  • Time for research: 3
  • Time for facilities building: 2 (ie: A Satellite Uplink now takes 28 days)
  • Cost of items and facilities: 2
  • Days in infirmary: 2.
  • Marathon don't work if tutorial is activated.
  • Item requirement for researches, foundry upgrades, cost of soldiers, interceptor costs, OTC upgrade costs remains the same.
    • This actually makes a strong case for making XCOM HQ in South America, as instant early interrogations to reduce other resarch times may put you ahead of the game. Or, if lucky with credits, in Europe, and building labratories to also reduce time.
  • Alien progress is slowed too. For example, first Mutons and Abductor UFOs show up in June, rather than May.
    • In effect: Storyline progression is greatly slowed, both on XCOM's end, as well as that of the aliens. But, as the experience requirements to level your soldiers remains the same, this means that you may end up with Colonels before you even see a Muton; the higher-level Abilities giving you a combative edge against the stronger aliens that appear later.

Unlocked after winning on Classic or higher difficulty

• Results Driven - A country will offer less funding as its panic increases.
  • Funding is cut by 20% from countries with level 4 panic, 40% when it's level 5.
• High Stakes - The rewards granted for stopping alien abductions are randomized.
  • This means the number of engineers or scientists (2 to 6) and amount of credit you get is randomized. You can see the rewards before launching the mission.
• Diminishing Returns - The cost of satellites increases with every one that is built.
  • This adds engineer requirement to make satellites too.
  • Cost goes up when you complete satellites, so try to make multiple satellite at once to save money.
  • Satellite build time is decreased.
• More Than Human - The psionic gift is extremely rare.

Unlocked only after winning Impossible

• Total Loss - Lose all gear from soldiers who die in combat.
• War Wariness - Overall funding levels drop inexorably with every month that passes.
• E-115 - Elerium stores will degrade over time.
  • Elerium has half-life of 15 days, which means you lose approx. 4.52% of Elerium stock per day. (or 1% per approx. 5hrs and 13mins.)
• Alternate Sources - The power requirements of all facilities are increased.
  • Power cost of all facilities are doubled. Base power (30 on classic) is doubled too, but power generators make same power.