Not true. If you do not meet the prerequisites of a prestige class you can't take levels in that class, you don't lose abilities from levels already gained.
Well I will be damned! I could have sworn it was the other way. Did that change since 3.0? So that means that Joe the Rogue could be converted to evil, join an assassin's cult, kill someone for no other reason than to join the assassins, gain a level in the assassin prestige class, then someone cures him of his evil (say from the helm of opposite alignment), Joe becomes good again, leaves the cult, but still can advance in the assassin class?
Anyhow, got another one.
1st ed AD&D. In a Dragon Mag, Gary Gygax released an article to modify the then newly released Unearthed Arcana, added a few errata, and notably added a few more multi-class options. One such was the Druid/Ranger. Probably to match his character Curly Greenleaf in the Gord the Rogue novels, but I am guessing here.
Rangers must be of Good alignment.
Druids must be of (true) Neutral alignment (ie. neither good nor evil).
So either the Druid/Ranger is different in alignment from every other Ranger, or is different in alignment from every other Druid.
On the other hand, it let half-elves be paladins, an expansion from the core.
A "party" inconsitancy (again courtesy of 1st ed). Low-level barbarians cannot be in the same character party as magic-users.
If we are just talking about "wackiness", 1st ed Monk cannot use flaming oil. AFAIK, no other character class in the game, in any edition of D&D, has this prohibition.
And with UA we begin to see the devaluing of the half-elf, a proud tradition that continued through many editions of the game. In core, half-elves had low level limits, but were the only class that could be cleric/magic-users, cleric/rangers, cleric/fighter/magic-users, well you get the idea. Other races that could be clerics were either a) the human, who could not multi-class, b) the half-orc, who couldn't be a ranger or a magic-user and had a lower max cleric level to boot, or c) races that only could be NPC clerics. UA blew off the "NPC only" limit, but left half-elves with their lower cleric level limits compared to dwarves, elves, etc. So now the half-elf lost a bit of it's niche protection. Probably they should have raised the cleric level limit of half-elves to at least be as good at being a cleric as one of their two parent races.
Speaking of half-breeds, in 1st ed., half-orcs are shorter than humans and shorter than orcs.
But I feel like I am beating on 1st ed AD&D, so here is a fun aspect to turning undead: Evil Clerics can turn paladins. No save. Payback is a bitch, as I found out to my cost as my brave paladin was forced to flee a combat.
In 3rd ed. this extends to some races vs. some cleric domains (scalyfolk vs. lizardy types, construct vs. warforged, etc.)
