I've been thinking more about solo (or duo, trio) characters and I don't think a straight XP modifier is going to work well. We all know that the experience costs for level 20+ are extreme but let me visualize just how weird the curve is even at lower levels. Here is a table of level requirements:
Code: Select all
Level 1: 0
Level 2: 1000 Δ 1000
Level 3: 3000 Δ 2000 ΔΔ 1000
Level 4: 6000 Δ 3000 ΔΔ 1000
Level 5: 10000 Δ 4000 ΔΔ 1000
Level 6: 15000 Δ 5000 ΔΔ 1000
Level 7: 21000 Δ 6000 ΔΔ 1000
Level 8: 28000 Δ 7000 ΔΔ 1000
Level 9: 36000 Δ 8000 ΔΔ 1000
Level 10: 45000 Δ 9000 ΔΔ 1000
Level 11: 55000 Δ 10000 ΔΔ 1000
Level 12: 75000 Δ 20000 ΔΔ 10000
Level 13: 100000 Δ 25000 ΔΔ 5000
Level 14: 150000 Δ 50000 ΔΔ 25000
Level 15: 200000 Δ 50000 ΔΔ 0
Level 16: 250000 Δ 50000 ΔΔ 0
Level 17: 300000 Δ 50000 ΔΔ 0
Level 18: 400000 Δ 100000 ΔΔ 50000
Level 19: 500000 Δ 100000 ΔΔ 0
Level 20: 1000000 Δ 500000 ΔΔ 400000
Level 21: 2000000 Δ 1000000 ΔΔ 500000
Level n: 1000000*(n-18) Δ 1000000 ΔΔ 0
Plotted:
This bizarre-looking second "derivative" demonstrates the problem. Before level 12, an exp_rate bonus is a somewhat smaller level bonus. (At 200 exp_rate, level 2 becomes a little under 3, level 4 becomes a little over 5, level 5 becomes a little under 7, level 7 becomes a little under 10; the +100% xp bonus is very roughly a +40% level bonus.) The curve of this bonus is a little weird, but only a little.
But as soon as we get to the point where the next level is 12, the value of exp_rate takes a sudden plunge, then it quickly happens again when the next level is 14, 18, 20, 21. You can straight up double incoming experience, and the advantage mostly vanishes when you reach level 20.
Furthermore, once you have a few skill points, the value of additional skill points drops sharply. The impact of the points getting a weapon skill to 5 (plus backstabbing), and the points to get your desired spells, is huge. The impact of the points you spend after that, tacking on a little extra damage or a little extra defense, is extremely small by comparison.
So you can give smaller-than-4 parties extra experience and extra skill points but it mainly helps them in the early game and has very little impact later. They will just hit their "soft cap" sooner - which is already lower than a full party's "soft cap" because the full party can use more attacks/spells at once due to having more cooldown slots.
Since we can draw over the builtin GUI, it's not very difficult to change the experience curve entirely. However that might be overkill and wouldn't change the skill point returns issue in any case. Perhaps level 19 or 20 being an effective cap is desirable.
In Grimrock 1's Toorum mode, sure, you got slightly more skill points and stats than a regular party, but the main things that made it not suck were 50% faster movement, 40% faster turns, and halved cooldowns. I think unique advantages like that are the only way to make solo/small parties feel good without totally overhauling the skill system. Of course an experience/level/skill point boost is better than nothing if you want to buff smaller parties.
UNRELATED: I just thought of a way to fix the custom "not enough energy" message: define a spell with a "valid" gesture that cannot actually be input by the player, like 121, and a manaCost of math.huge. When a champion tries to cast a spell pack spell with a variable energy cost, and they don't enough energy, return false from that onCastSpell hook but call champion:castSpell(121). Then you get the proper effects for casting a spell without enough energy.
(but who cares about that! You get it because the gods wanted it, that's the story 
)
