The Tavern

According to another thread, the chance of spawning hostile servants is:


Some people have been saying to only train invocations to 12, but based on this, I think I would want to take it to 14 before turning it off.

Comments:
- The effect of piety is rather small. Even at 200 piety, this only reduces the odds by 8%, the same as having 2 levels in invocations.
- I'm often somewhere at *****. piety when I summon a greater servant, so I'd guess about 150 piety, or -6%. That leaves 64% to be reduced by invo skill.
- 64% / 4% = 16, so level 16 would guarantee non-hostile summons.
- At invo 12, there's still a 16% chance of hostile. That's basically 1/6, the same as playing russian roulette.

Because the odds are that I'll be summoning a greater servant when I'm in the middle of a fight that is already tougher than I can probably handle, I really don't want to gamble on a 1/6 chance of adding a hostile balrug or executioner to the mix.

Even if you survive the balrug, in my last such surprise, I lost a number of enchant armour and enchant weapon scrolls to that demon whip of flame, which seems to also have a "reaching" brand. Nice, if only I could take it off the balrug.

Based on the formula, there are not "diminishing returns" after invo 12 - the returns continue until invo 15 and 16, at which point there are NO more returns, at least for summoning servants (unless you have low piety, but in that case you are only summoning minor servants).

I think I would take it to 14 and then turn it off. At piety ****** that's only a 4% chance of hostile, and then over the course of the game it may get trained to 15 or 16 while turned "off", which just puts the icing on the cake. This way the remaining trickle of XP going into invocations is not a waste.

Even with 16+ invocations I still summoned hostile 1s with my necromancers/chaos knights. IIRC there's always a 5% chance that Makhleb's servants may be hostile (same as the Summon Greater Demon spell). I think only high power Pentagram cards have 100% guaranteed friendly greater demons.

Okay, so if it bottoms out at 5%, that's fine, it's still better than 16%. I'll take 1/3 the risk of hostile demons any day!

All I know is, I was still seeing hostile demons pretty regularly with invo 12 (it felt like about 1/4 to me, but it could have been 1/6). I'll try invo 14 and see how that goes.

In 0.8, the skill disabling scales with skill level. Instead of training once in 4, it's now once in (3 + skill_level). Which means a level 14 skill gets trained only once in 17. So it will probably never reach lvl 15.

Also, don't wait until the poop has hit the fan before summoning. Tension (allegedly) doesn't come into play for Makhleb, but the nature of the RNG itself pretty much guarantees that if you're in bad shape and are trying just to even the odds, you'll pop out a hostile Executioner or Balrug. Summon when the poop is en route to hitting the fan, and if the summon comes out hostile, you'll still be in decent enough shape to deal with it.

70 - (Piety/25) - (Invo skill * 4) is the failure rate of the invocation itself. Failing this check means the ability is not used.
If random2(20 + you.skills[SK_INVOCATIONS] * 3) > 3, the summon is friendly. Lesser and greater servants both use the same friendliness check so lesser is not more likely to succeed at low invocations skill.

Thanks. If I read that right, there's a 3 in (20+Invo skill) chance of summoning a hostile?

So with invo 10, it's 3 in 30, or 10% chance of summoning hostile.

Hmm. There's not much incentive to training invocations further then.

I haven' checked the source, but he said 3 in (20+Invo*3). So for invo 10, that's 3 in 50 or 6%.