How to Trade Up to M4A1-S | Basilisk
M4A1-S | Basilisk drops from Operation Vanguard Weapon Case, so any contract that can produce it needs 10 Mil-Spec skins from that same case. Here is what the contract costs, what else it can land on, and the input float you need for each exterior.
- Odds per contract
- 25% 1 in 4
- Contract cost from
- $6.20 10 × cheapest input
- Expected value
- $3.53 mean of the outcome pool
- Margin
- -43.1% $-2.67 per contract
This contract is EV-negative. The cheapest ten inputs cost $6.20 and the outcome pool averages $3.53, so it loses $2.67 per contract on average even before you account for hitting the wrong skin.
The contract
10 inputs, all Mil-Spec, all from Operation Vanguard Weapon Case. Concentrating every input in one case is what keeps your odds at 25% — mixing cases splits the probability across both pools and lowers your chance at M4A1-S | Basilisk specifically.
MAG-7 | Firestarter
G3SG1 | Murky
MP9 | Dart
G3SG1 | Murky
UMP-45 | Delusion
MAG-7 | Firestarter
MAG-7 | Firestarter
MP9 | Dart
UMP-45 | Delusion
MP9 | Dart
G3SG1 | Murky
MAG-7 | Firestarter7 further eligible inputs are available — open the reverse trade-up finder to price a full contract against your own inventory.
What else this contract can land on
A contract from Operation Vanguard Weapon Case draws uniformly from every Restricted Rifle skin in the pool, so M4A1-S | Basilisk is one of 4 equally likely results. These are the other 3.
| Outcome | Odds | Cheapest price |
|---|---|---|
| M4A1-S | Basiliskyour target | 25% | $7.48 |
| M4A4 | Griffin | 25% | $2.78 |
| Glock-18 | Grinder | 25% | $2.25 |
| Sawed-Off | Highwayman | 25% | $1.59 |
Input float for each exterior
CS2 normalises float across a trade-up: each input’s float becomes a 0–1 position inside its own range, those are averaged, and the average is applied to M4A1-S | Basilisk’s range of 0.00–0.68. To land a given exterior, your ten inputs must average the normalised float below.
| Target exterior | Output float | Required avg. input float |
|---|---|---|
| Factory New | 0.0350 | 0.0515 |
| Minimal Wear | 0.1100 | 0.1618 |
| Field-Tested | 0.2650 | 0.3897 |
| Well-Worn | 0.4150 | 0.6103 |
| Battle-Scarred | 0.5650 | 0.8309 |
“Not reachable” means M4A1-S | Basilisk’s own float range never enters that exterior band — no combination of inputs can produce it.
What M4A1-S | Basilisk is worth right now
Worth comparing against the contract cost above before you commit: buying the skin outright is frequently cheaper than rolling for it.
| Exterior | Price | vs. contract cost |
|---|---|---|
| Field-Tested | $7.48 | +$1.28 |
| Battle-Scarred | $7.57 | +$1.37 |
| Well-Worn | $9.53 | +$3.33 |
| Minimal Wear | $9.81 | +$3.61 |
| Factory New | $24.10 | +$17.90 |
Build this contract
Price a full ten-slot contract against live inputs, set your own float values, and see the outcome odds update as you go.