How to Trade Up to M4A4 | Spider Lily
M4A4 | Spider Lily drops from Operation Riptide 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
- 20% 1 in 5
- Contract cost from
- $5.60 10 × cheapest input
- Expected value
- $3.32 mean of the outcome pool
- Margin
- -40.7% $-2.28 per contract
Buying is cheaper than rolling. A Battle-Scarred M4A4 | Spider Lily costs $5.05 outright, against $5.60 for a contract with a 20% chance of producing one. Trade up for the process, not the value.
The contract
10 inputs, all Mil-Spec, all from Operation Riptide Case. Concentrating every input in one case is what keeps your odds at 20% — mixing cases splits the probability across both pools and lowers your chance at M4A4 | Spider Lily specifically.
Dual Berettas | Tread
PP-Bizon | Lumen
Dual Berettas | Tread
G3SG1 | Keeping Tabs
AUG | Plague
MP7 | Guerrilla
USP-S | Black Lotus
MP7 | Guerrilla
USP-S | Black Lotus
AUG | Plague
AUG | Plague
G3SG1 | Keeping Tabs12 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 Riptide Case draws uniformly from every Restricted Rifle skin in the pool, so M4A4 | Spider Lily is one of 5 equally likely results. These are the other 4.
| Outcome | Odds | Cheapest price |
|---|---|---|
| M4A4 | Spider Lilyyour target | 20% | $5.05 |
| MP9 | Mount Fuji | 20% | $4.48 |
| Five-SeveN | Boost Protocol | 20% | $3.09 |
| FAMAS | ZX Spectron | 20% | $2.10 |
| MAG-7 | BI83 Spectrum | 20% | $1.89 |
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 M4A4 | Spider Lily’s range of 0.00–1.00. 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 | 0.0350 |
| Minimal Wear | 0.1100 | 0.1100 |
| Field-Tested | 0.2650 | 0.2650 |
| Well-Worn | 0.4150 | 0.4150 |
| Battle-Scarred | 0.7250 | 0.7250 |
“Not reachable” means M4A4 | Spider Lily’s own float range never enters that exterior band — no combination of inputs can produce it.
What M4A4 | Spider Lily 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 |
|---|---|---|
| Battle-Scarred | $5.05 | −$0.55 |
| Well-Worn | $5.41 | −$0.19 |
| Field-Tested | $7.30 | +$1.70 |
| Minimal Wear | $12.41 | +$6.81 |
| Factory New | $58.78 | +$53.18 |
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.