Pluginy AMX Mod X

Rewards the first kill of every round with a sound, a coloured announcement and bonus HP and/or cash.

Put a cash bounty on a player's head; it shows in the HUD and pays the killer, with an anti-farm cooldown.

Tracks damage per attacker and credits the top assister above a threshold when a victim dies, optionally paying a cash reward.

Replace the CS economy: fixed start money, per-kill and headshot rewards, and a flat per-round income for everyone.

Rewards the planter, the defuser and (on detonation) the whole Terrorist team with money, health and armor, once per round.

Extra money and HP for rescuing a hostage, plus a CT team bonus when all hostages are saved.