Return on Investment: A concept
When we look at mana generator cards in MW, you spend anywhere from 4 to 6 Mana to increase your mana income by 1. Therefore, your "return on investment" (RoI) is either 1/4, 1/5, or 1/6 per round. This can also be expressed as a 4, 5, or 6 round break-even (BE).
You could argue that a 5-round BE is "average". Anything that breaks even in 4 or less rounds is an above-average investment, while anything that takes 6+ rounds is a below-average investment.
However, in the late game this assumption falls apart. If both players are low on health and could die on any given round, it is far better to blow all your mana on immediate damage or healing. Never forget that an investment that breaks even in X rounds sucks if the game ends in X-1 rounds.
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What a lot of people don't realize is that you can assess damage and actions in a similar fashion:
For example, a Fireball costs 8 Mana + 1 Quick Action to roll 6 dice and ~0.93 Burns. (approx. 9 damage vs. 0 armor, 6 damage vs. 5 armor)
Meanwhile, a Ghoul Rot on Mage costs 8 Mana + 1 Quick Action to deal 2 direct damage per round.
Looking at these numbers, Ghoul Rot takes anywhere from 3 to 5 rounds (depending on enemy Armor) to "break even" with Fireball.
So just by examining the relative value of the two spells, Ghoul Rot is an "average investment" relative to Fireball against 0 armor, but becomes a "very good investment" against high Armor. Again, whether or not Ghoul Rot is a superior play depends on the other guy's total HP. If he's got 3 HP left, a Fireball is very likely to kill instantly (0 rounds) while Ghoul Rot will still take 2 rounds. The fact that Ghoul Rot breaks even after 3 rounds is irrelevant if the enemy player is dead in 2.
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Okay, so now let's apply this concept to creatures:
A Fireball costs 8 Mana + 1 Quick Action to roll 6 dice and ~0.93 Burns. (approx. 9 damage vs. 0 armor, 6 damage vs. 5 armor)
A Skeleton costs 8 Mana + 1 Full action, and starting 1 round later it can roll 4 dice per round. (approx. 4 damage vs. 0 armor, 2 damage vs. 5 armor)
Regardless of enemy Armor, the Skeleton breaks even after 4 rounds. This makes it an "above average" investment in damage. So why use attack spells at all? Well, your opponent could kill the skeleton. He could daze or stun it. He could put an Iron Golem on Guard. All of these things would prevent the Skeleton from effectively using its damage dice, whereas a Fireball would always get its damage dice in.
In addition, the Skeleton uses a full action. If you weren't summoning, you might have used that full action to swing 4 or more damage dice (often much more). We'll talk more about this later.
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Now let's take this concept to the next level!
There are two enemy Falcons in my zone, pecking me for 3+3 dice per round. How worthwhile is a Ring of Fire?
A Ring of Fire has a 60% chance to one-shot a Falcon (it doesn't get to attack you this round). The surviving Falcons will get to attack you for at least 1 round.
- Surviving Falcons will have a 50% chance to have 1 or more Burn tokens.
- Of the Burning falcons ~67% of them will Burn to death over ~1.5 rounds.
- Overall, you will kill ~60% of Falcons instantly, ~10% of Falcons after 1 round, ~5% of Falcons after 2 rounds, and ~25% of Falcons will survive.
The traditional calculation says you're spending 9 Mana to kill an average of 1.5 Falcons (7.5 Mana) so it's not worth it. But what if we analyze it based on RoI, reducing the enemy's damage dice?
- On average, a Falcon struck by Ring of Fire will deal 1.2 damage dice the first round, 0.9 damage dice the second round, and 0.75 damage dice every round afterward.
- Compared to an unharmed Falcon, this is a 1.8 damage dice savings on the first round, 2.1 on the second, and 2.25 on the third.
- 9 mana is 1 more than a Fireball, which against an unarmored Mage would deal ~9 damage over 2 rounds. So for the purposes of our break-even analysis, let's assume that casting Ring of Fire allows your opponent to nuke you for ~10 damage dice.
* By the end of round 1, the Ring of Fire "saves" you 3.6 damage dice.
* By the end of round 2, the Ring of Fire "saves" you 7.8 damage dice.
* By the end of round 3, the Ring of Fire "saves" you 12.3 damage dice.
So even against just 2 Falcons, Ring of Fire has an extremely rapid 3-round BE! Because Falcons have a very high ratio of damage to health, you really want to kill them quickly, even if you have to use a "non mana efficient spell" to do so. But does this mean we should always use a zone-attack every time there are 2 Falcons in a zone?
Don't be silly! Ring of Fire may have a 3 round BE, but there are much less expensive ways to kill Falcons! If you can kill the Falcons with a Lash of Hellfire instead, you don't need to worry about "breaking even" because you never spend any mana in the first place.
Always remember: You can calculate break-even points for an investment, but achieving an objective for no cost is always superior to spending mana on an investment.
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Can we place a relative price on Quick Actions, and Full Actions?
The answer is: Sort of.
Compared to a Mana Crystal (+1 channeling with no action), a Battleforge or Thoughtspore has 1 channeling and 1 quick action, but costs 8 mana instead of 5. This is a +60% relative mana cost.
Does this mean that a quick action is worth 0.6 Mana? Don't be silly. A spawnpoint or familiar usually doesn't use its action every single round. Spawnpoints are additionally limited by range, and familiars are easily killed.
My best guess is that Quick Actions can be "priced" at ~2 Mana, while Full Actions are "priced" at around 4 Mana. Using these numbers makes Spawnpoints and Beastmaster passive seem vastly more mana efficient than you'd usually think.
However, you also have to realize that actions cost Mana. If you are mana starved, all the spawnpoints and familiars in the world are useless. Players are only willing to give up Mana for Actions if they have enough Mana to take those actions.
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What does this all mean?
Many times in Mage Wars, a player has the opportunity to choose between an action with immediate effects (such as a Battle Fury or Fireball) and an action with delayed effects (such as summoning a creature or casting an enchantment). Taking the latter action is like making an investment toward later rounds of the game.
In each of these situations, you should try to think about the following:
1) Is the game about to end? If not, then:
2) Is there a way to achieve the same objective without an investment? If not, then:
3) If you make an investment, will it pay off in a reasonable timeframe? If so, then:
4) Does your opponent have an investment with a stronger payoff than yours?
5) If so, then focus on destroying his investments. If not, then focus on making your own investments.
For example, for a Wizard paying 4 mana per mana crystal sounds like a pretty sweet RoI. However, if an enemy Beastmaster is summoning Foxes in your face, 3 dice per round is even sweeter for him than 1 Mana per round is for you.
Instead of focusing on your own investment, your best strategic option is to focus on destroying your opponent's investments. Throw out a Ring of Fire, a Suppression Cloak, a Circle of Lightning or a Darkfenne Hydra, and you'll rapidly cut his dog swarm down to size.
On the other hand, if your opponent is investing in 5-mana Crystals while you are investing in 4-mana Crystals, you are definitely coming out ahead. You should feel comfortable sitting back and continuing to build up - investing for a future full of big creatures and attack spells.