I too get crashes on the character selection SOMETIMES, but since it's only there, it's as good as no crash.
Tried a Letty build and I admit that it's very fun to play, all around AoE cold spells. I'll try giving a brief review on her skills and whatnot. It's hard to decide what to max as majority of the skills are great. Though I'm level 25, thus some of this might not necessarily carry over further in the game.
Base bonus: +0.5%*Base Snow to Maximum Cold resistance.
Quite disappointing and most assuredly not worth putting points into base Snow for the purpose of this thing only. A maximum of 87.5% of resistance to cold doesn't make that much of a difference in comparison to 75%. Only good if you got max. resistance increasing runes, to help you achieve 100%.
White Sign "Undulation Ray"
Very effective for a spell acquire-able this early and given the nature of the library fairy, it isn't exactly very mana demanding either. Projectiles flying like those of paladin's Blessed Hammer, freezing the opponents solid is ludicrous. Best for dealing with the creeps accompanied by shamans as there is 100% chance to crush the opponent if it dies from this skill. Though some creeps graze it and it may require positioning for best use. :V
Cold Sign "Lingering Cold"
Your typical Holy Freeze. Never gets old.
Mystic Sign "Table-Turning"
CD: 1s; Shares cooldown with "Northern Winter", but also puts a cooldown of 1s on all other activities.
Frozen Orb-ish grand AoE damage with only a small delay between casting one another, deal with the groups effectively and you can affect the area you desire frequently, without the fear of being backdoored for some reason.
Winter Sigh "Northern Winter"
CD: 8s; Shares cooldown with "Table-Turning", but also puts a cooldown of 1s on all other activities.
Blizzard spell with insane mana cost (133 + 33 per skill-up), though it's cooldown denies you from burning your mana (at lower ranks). Lets you spam Undulation Ray or Cold Snap while it showers the selected area, unlike "spammable" Table-Turning.
Cold Sign "Cold Snap"
The only not AoE spell in this skilltree, bouncing (off of enemies) ice spike, damaging only those it directly hits. The minimum to maximum damage difference is quite big, but it's mana cost is really low for the damage it can cause even on rank 1. It's casting time is pretty long though and when it technically doesn't have a cooldown, it's only slightly faster than Table-Turning. Guess this is fixable by "faster spell casting" bonus on some item.
Letty generally appears to be balanced, leaning towards slightly OP with all the slow she can cause, though the damage isn't really a rooftop. Especially since cold immunity renders this whole tree useless. All in all, I don't see any place for adjustments.
Now it's a question time. Does LoM have any possibility for the fairy to actually break the immunities? The only thing that comes to mind is Hi+Na runeword, but I don't know if it grants all them Hina skills or not.
I also wonder what do the "unplayable character" runewords grant (beside the basic buffs from the runes), but I'll leave that to empirically discover by myself. Ooh scary scary.
