Basically you trade out half your character feats to get class abilities at those levels instead. For example:
Cleric:
A character who chooses cleric as her secondary class gains the following secondary class features.
Deity: At 1st level, she must select a deity within one alignment step of her own. She gains the cleric's aura, bonus languages, code of conduct, and restriction from casting spells of opposed alignments. She also gains the cleric's spontaneous casting ability, which she can use with any prepared casting classes that have the appropriate spells on their spell lists.
Domain: At 3rd level, she selects one domain her deity grants, gaining that domain's 1st-level granted power, treating her character level as her effective cleric level.
Channel: At 7th level, she gains the ability to channel energy as a cleric of her character level – 6 a number of times per day equal to her Charisma modifier + 1.
Improved Channel: At 11th level, her ability to channel energy improves to that of a cleric of her character level – 4.
Improved Domain: At 15th level, she gains the additional domain power of her chosen domain, treating her character level as her effective cleric level.
Greater Channel: At 19th level, her channel energy ability improves to that of a cleric of her character level – 2.
Oracle:
A character who chooses oracle as her secondary class gains the following secondary class features.
Mystery: At 1st level, she must select a mystery. She never qualifies for the Extra Revelation feat.
Curse: At 1st level, she must select a curse. She gains all effects of the curse, treating her effective oracle level as equal to 1/2 her character level.
Revelation: At 3rd level, she gains one of the following revelations from the list of those available to her mystery as an oracle of her character level – 6 (minimum 1). She must have an effective oracle level high enough to select the revelation.
Battle: Battlecry, battlefield clarity, combat healer, iron skin, resiliency, skill at arms, surprising charge, war sight.
Bones: Armor of bones, bleeding wounds, death's touch, near death, raise the dead, resist life, soul siphon, spirit walk, undead servitude, voice of the grave.
Flame: Burning magic, fire breath, form of flame, gaze of flames, heat aura, molten skin, touch of flame, wings of fire.
Heavens: Coat of many stars, dweller in darkness, guiding star, interstellar void, lure of the heavens, mantle of moonlight, spray of shooting stars, star chart.
Life: Channel, delay affliction, energy body, enhanced cures, healing hands, life link, lifesense, safe curing, spirit boost.
Nature: Erosion touch, life leach, natural divination, speak with animals, spirit of nature, transcendental bond, undo artifice.
Stone: Acid skin, clobbering strike, crystal sight, earth glide, mighty pebble, rock throwing, shard explosion, steelbreaker skin, touch of acid.
Waves: Blizzard, fluid nature, fluid travel, freezing spells, ice armor, icy skin, punitive transformation, water form, water sight, wintry touch.
Wind: Air barrier, gaseous form, invisibility, lightning breath, spark skin, thunderburst, touch of electricity, vortex spells, wind sight, wings of air.
Orison: At 7th level, if she has a Charisma score of 10 or higher, she chooses an oracle orison to cast as a spell-like ability at will. She uses her character level as the caster level and Charisma as the orison's key ability score.
Curse Focus: At 11th level, she adds 5 to her effective oracle level for the purposes of determining her curse's effects.
Improved Revelation: At 15th level, she gains one additional revelation.
Greater Revelation: At 19th level, she gains one additional revelation.
I know we've discussed the Huge scorpion venom here before, where it is one of those "before Pathfinder" modifications in the book. The poison is literally "Huge scorpion venom; DC 18 Fort Save, 1d6/1d6 Con damage".
The new version in the Bestiary is "Poison (Ex) Sting—injury; save Fort DC 17; frequency 1/round for 6 rounds; effect 1d2 Strength damage; cure 1 save. The save DC is Constitution-based and includes a +2 racial bonus."
I believe we are all in agreement that the first version as written is a PC-killer. Fail 2 saves and most people who are not a Dwarf with CON 15 and the Heroic Recovery feat are dead. That's pretty harsh for a book designed for Levels 6-7. We've been hit twice now with this killer poison, but every Carrion Guard you have come across has had those poison arrows, which means 2/3s of your encounters in the House of the Beast could have been with this poison Save.
So what's a by-the-book GM to do? I can't nerf the poison, we've applied it already on the Western Stairs. But I can spread the antitoxin around. Every Carrion Guard fought so far has had 2 vials of antitoxin on them. Antitoxin gives you a +5 alchemical bonus on Fortitude saving throws against poison for 1 hour. Not +4. +5, according to the CRB. I can also be verbose as a GM and tell you when a Carrion Guard takes "special care" while loading a longbow. Nobody needs to rush into battle and everyone's had plenty of time to pass around the antitoxins and drink them before opening the doors.
But the players have to step up too. You've leveled mid-game, which means somebody could have picked up delay poison (bard 2, cleric 2, druid 2, paladin 2, ranger 1). Let's see, paladin (oracle) - check, druid - check. Granted, it would only delay the effects 6 hours or so, but that might be long enough for the players to find an alchemist's lab somewhere, or for the GM to drop a neutralize poison potion, or a cloak of resistance +1, or something else to help with the Fort save. (Where's all these antitoxins and injection spears with drugs in them coming from?)
And with the real Save vs. death rolls, as loath as I am in bending any rules, you can always take the GM's roll. It might be better. It might be worse. Even the GM can't control the dicebot here on the Pazio boards. But until the book grants scrolls of Raise Dead et al, it's the best I can do in preventing PCs from becoming deadweight cargo. The last thing I want as a GM is a player twiddling their thumbs for weeks in real life.
Also in 3.5, poison was 2 rolls, so onset was 1d6 CON with a save...after a few minutes it was another save and another 1d6CON damage. It wasn't 1d6CON/round for 6 rounds.
Pathfinder went with smaller damage and per round effect instead of the annoying to remember "after 10 minutes" make another save poison rules.
PG-13, folks! Please! I know it's impossible for 'rated G', given the blood & gore, but keep things to innuendo. We've got kids under 18 reading this board.
NG Female Human Druid 6 | HP 44/44 | AC/Touch/Flat 18/12/16 | Fort/Ref/Will +5/+3/+8 | Init: +2 | Percep: +15
One...two...three and a quarter!
I gotta date with the Generals' dwaughter...
General, general, he's a sucka:
He doesn't know that i'm-a-gonna--
LEFT! Left... Leftcha right left!
NG Female Human Druid 6 | HP 44/44 | AC/Touch/Flat 18/12/16 | Fort/Ref/Will +5/+3/+8 | Init: +2 | Percep: +15
Yes I'd like to bone up on a little healing power for you all. You guys really don't need a damage dealing druid as much, and I like RPing the healer...
Male Male(Human) Class Level Fighter 12 Weapon Master | HP 93/122| AC/Touch/Flat 24/15/19 | Fort/Ref/Will 8/8/6| Init: +6 | Percep: +12 BAB 12 | CMB +17 | CMD 30 (33 if kukri related)
The great thing about prepared casters is they can be whatever they need to be for the day. Yesterday it was a lightning slinging damage dealer. Today a little lesser restoration is most helpful.
NG Female Human Druid 6 | HP 44/44 | AC/Touch/Flat 18/12/16 | Fort/Ref/Will +5/+3/+8 | Init: +2 | Percep: +15
Mabe we will find a portal to some other dimension down here. Or a genie who will finally grant Yazi her wishes. Or some other diabolically cool thing...No pressure GM! Haha!
Somebody added a "tunnel?" with an arrow pointing to the eastern tunnel as described. Yes, that's it. I added a half-circle to both the east and west tunnel entrances.
And I've got Vacation Bible School at my church this week, and I'm one of the adult helpers. It might limit my posts to once a day, but I'll try to be more responsive than that.