The Apu is based of the Capybara. I will give more of their lore when I finish the species of Kalsier. Right now, it is mostly a slightly modifide Halfling.

The Apu Traits

Size: Small Creature type: Humaniod Speed: 40ft

Swimmer.  You have a swim speed equal to your walking speed, and can hold your breath for up to 10 minutes.

Calm as an Pound. You have Advantage on saving throws you make to avoid or end the Frightened condition.

Nimbleness. You can move through the space of any creature that is a size larger than you, but you can’t stop in the same space.

Luck. When you roll a 1 on the d20 of a D20 Test, you can reroll the die, and you must use the new roll.

Naturally Stealthy. You can take the Hide action even when you are obscured only by a creature that is at least one size larger than you.

Crowd Calmer

Racial Feat Requirements: 4th level, species is a Apu

You can cast Sanctuary on yourself a number of times equal to your proficiency bonus per long rest. Additionally you may cast Calm Emotions once per long rert.

To cast these spells you do not need to use material components, and the verbal incantations are soothing words.

D&D combat can become quite stale by the fourth round, but I have here something that can help.

It is really quite simple, every three rounds of combat switch something up. Here are some examples:

• While the players are raiding a thieves guild safe-house, the guard arrives and mistakes the players as another group of thugs.
• After a failed ambush, the Kobolds retreat, leading combat into a new environment.
• The arch-mage has been saving their uses of a powerful spell. In the event that combat goes for nine rounds, as a DM you need to end combat, even if just temporarily. Maybe the enemies flee creating a chase scene, or maybe try to negotiate, creating an interesting social interaction. Anything to create a break from combat. If combat starts again, it will be after a break and probably under new circumstance.

One last thing, this is not something you actively tell your players you are doing, as it may break immersion a little. As Sun Tzu said “Let your plans be dark and impenetrable as night..."

"...and when you move, fall like a thunderbolt."